50 Dead, Islamic Terrorism Tie Eyed In Orlando Gay Bar Shooting

7:11 p.m.

The top Democrat on the House Intelligence Committee tells The Associated Press that investigators have not yet found evidence of direct communication between the Orlando nightclub gunman and Islamic State members overseas.

Rep. Adam Schiff has been briefed multiple times by federal law enforcement. He says it is possible that Omar Mateen was self-radicalized but not "under the command and control of ISIS."

The California congressman says that could change and that it's too early to know whether there was something that could have been done to prevent the attack.

The FBI investigated Mateen in 2013 after he made inflammatory comments to co-workers alleging possible ties to terrorists. The following year, the agency looked into potential ties connecting Mateen to Moner Mohammad Abusalha, the first American to carry out a suicide attack in Syria.

He was cleared after both investigations.

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6:40 p.m.

Vice President Joe Biden released a statement Sunday evening in regards to the mass shooting, calling it "an act of pure hate and unspeakable terror."

"They were our brothers and our sisters; our friends, neighbors, and loved ones. In the coming days, we will learn more about these fifty souls and the lives they lived and the world they made better," Biden said.

He offered condolences to the victims and their families.

"The violence is not normal, and the targeting of our lesbian, gay, bisexual, and transgender Americans is evil and abhorrent," Biden said.

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6:31 p.m.

The City of Orlando has added a seventh person to their list of the deceased: Luis S. Vielma, 22 years old.

The entire list can be seen here.

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6:12 p.m.

CBS affiliate WFOR tweeted video from Orlando resident David Ward. The video reportedly captures the moment SWAT teams shoots and kills the suspected gunman in the Orlando mass shooting.

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6:10 p.m.

A woman whose cousin was shot at a gay Orlando nightclub says he is in critical condition at a hospital.

LaToya Hall says her cousin Keon Carter was in the Pulse club early Sunday when a gunman opened fire and killed 50 people and wounded about 50 others.

Hall says her cousin is alert at Orlando Regional Medical Center. She says he tried to hold her hand and turn his eyes to look at her.

Hall says many people are having trouble locating victims because they are being listed under fake names.

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6:05 p.m.

The City of Orlando is asking for a hold on vigils being planned in the city.

In a tweet, the city asked that vigils be put on hold because of the strain it puts on its limited resources, which need to be dedicated to the victims and their families.

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5:53 p.m.

A U.S. intel source tells CBS News that Mateen called 911 during the shooting from the bathroom. They called him back and that is when he pledged alliance to ISIS and al Baghdadi.

The source says he made two foreign trips, one in 2011 to Dubai and one to Saudi Arabia in 2012.

He was not on a current watch list. He was on the Terrorist Screening database when the FBI was questioning him. Source tells CBS News he was removed when the FBI closed their investigation.

The 2013 investigation began when Mateen told co-workers and others he knew the Tsarnaev brothers.

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5:45 p.m.

The ATF tweeted a photo of two guns, saying the guns were similar to those traced to the Orlando shooting.

"Guns traced in #Orlando shooting: .223 caliber AR type rifle and 9mm semiautomatic pistol. Similar to those pictured," the tweet read.

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5:21 p.m.

The City of Orlando has released names of victims of the nightclub shooting whose next of kin have been contacted.

The list will be periodically updated on www.cityoforlando.net/blog/victims/ as those who died are identified and families and loved ones notified. The city gave no additional information other than the names.

-Edward Sotomayor Jr.

-Stanley Almodovar III

-Luis Omar Ocasio-Capo

-Juan Ramon Guerroro

- Eric Ivan Ortiz-Rivera

- Peter O. Gonzalez-Cruz

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4:50 p.m.

The Orlando mayor says of the 50 victims who died from the shooting at a gay nightclub, 39 were killed at the club and 11 people died at hospitals.

Orlando Mayor Buddy Dyer says at first officers mistakenly thought the gunman had strapped explosives to the dead victims and that the club was boob-trapped. A bomb robot sent back images of a battery part next to a body.

Dyer says that held up paramedics from going in until it was determined it was something that fell out of an exit sign or a smoke detector.

The robot was sent in after SWAT team members put explosive charges on a wall and an armored vehicle knocked the wall down in an effort to rescue hostages.

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4:35 p.m.

A law enforcement official says the gunman who killed 50 people at a gay nightclub made a 911 call from the club, professing allegiance to the leader of the Islamic State, Abu Bakr al-Baghdadi.

The law enforcement official is familiar with the investigation but was not authorized to discuss the matter publicly and spoke on condition of anonymity.

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4:05 p.m.

The FBI says agents twice investigated the man who killed 50 people inside a gay nightclub, but closed those cases after interviewing him.

FBI agent Ronald Hopper said Sunday that Omar Mateen had been interviewed in 2013 and 2014. Hopper said agents first investigated Mateen after he made inflammatory comments to co-workers alleging possible ties to terrorists.

Mateen was interviewed twice and, when investigators were unable to verify the details of his comments, the FBI closed the probe.

In 2014, the agency looked into potential ties connecting Mateen to Moner Mohammad Abusalha, the first American to carry out a suicide attack in Syria. Like Mateen, Abusalha lived in Fort Pierce, Florida.

Hopper says agents determined that contact was minimal and did not constitute a substantive relationship or a threat at that time.

Mateen was 29 years old and born in New York. The FBI says he referred to the Islamic State in a 911 call before the slayings.

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4:00 p.m.

The ex-wife of the man authorities say killed 50 people at an Orlando nightclub says he beat her repeatedly while they were married.

Omar Mateen's ex-wife told The Washington Post that she met him online about eight years ago and decided to move to Florida and marry him. The ex-wife, who wasn't named in the report, says at first the marriage was normal, but then he became abusive.

They were together for only a few months and her parents intervened when they learned Mateen had assaulted her. She says he wasn't very religious and gave no signs of radical Islam. She said he owned a small-caliber handgun and worked as a guard at a nearby facility for juvenile delinquents.

Mateen's ex-wife said his family was from Afghanistan, but her ex-husband was born in New York. His family later moved to Florida.

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3:30 p.m.

Mateen legally purchased in the last few days the two guns he allegedly used to kill 50, and wound 53 more at a gay night club in Orlando, authorities said Sunday.

The FBI confirmed at a press conference Sunday afternoon that federal authorities twice looked into Mateen in the past. In 2013 Mateen allegedly made inflammatory statements referencing terrorism while talking to coworkers, and in 2014 he was questioned because of what FBI Special Agent Ron Hopper called a possible connection to a suicide bomber.

Hopper said agents contacted Mateen three times, but ultimately determined there was no reason to pursue an investigation.

"Those interviews turned out to be inconclusive so there was nothing to keep the investigation going," Hopper said.

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3:00 p.m.

The suspected Orlando nightclub gunman had been licensed as a private security officer in Florida.

State records show suspected shooter Mateen held the firearms license since at least 2011. It was set to expire in September 2017.

It wasn't immediately clear where, if anywhere, Mateen had worked as a security officer. An armed guard license in Florida requires 28 hours of classroom training by a licensed instructor.

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2:50 p.m.

The terror group ISIS has claimed responsibility for the attack Sunday morning at a gay nightclub, which left 50 dead and 53 injured, according to the latest estimates from authorities. The group's Amaq Agency quoted a source in claiming that the shooting "was carried out by an Islamic State fighter."

ISIS has in the past claimed responsibility for attacks that did not originate within their command structure or territory.

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2:30 p.m.

President Barack Obama says the worst mass shooting in U.S. history is a further reminder of how easy it is for someone to get a weapon that allows them to shoot people in a school, in a house of worship, a movie theater or a gay nightclub.

Speaking from the White House, Obama says the United States has to decide if that is the "country we want to be." He says that doing nothing is a decision as well.

The shooting has thrust the topic of gun control back into focus as a presidential election nears.

Presumptive Democratic nominee Hillary Clinton has called for expanding background checks to sales at gun shows and online purchases, and for reinstating a ban on assault weapons. Presumptive Republican nominee Donald Trump has said the existing background check system should be fixed, not expanded, and that assault-weapons bans do not work.

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2:15 p.m.

A law enforcement official has confirmed to CBS news senior investigative producer Pat Milton that shooting suspect Mateen made the Hajj, an Islamic pilgrimage to Mecca, Saudi Arabia in March 2012.

President Barack Obama said at a press conference Sunday that the shooting was an "act of terror" and an "act of hate."

He said the FBI is investigating it as an act of terrorism and that no effort will be spared to determine whether the shooter was affiliated with terrorist groups.

Staff at the Islamic Center, a mosque in Ft. Pierce, Florida, confirmed to CBS News that Mateen, 29, has worshiped at the facility regularly for several years.

The mosque condemned the attack in a statement released Sunday afternoon:

We condemn this monstrous attack and offer our heartfelt condolences to the families and loved ones of all those killed or injured. The Muslim community of Fort Pierce joins our fellow Americans in repudiating anyone or any group that would claim to justify or excuse such an appalling act of violence.

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2:00 p.m.

A security company has confirmed that Orlando shooting suspect Mateen was employed as a guard before he allegedly killed 50 and wounded 53 early Sunday. The company, G4S, released a statement Sunday afternoon:

We are shocked and saddened by the tragic event that occurred at the Orlando nightclub. We can confirm that Omar Mateen had been employed with G4S since September 10, 2007. We are cooperating fully with all law enforcement authorities, including the FBI, as they conduct their investigation. Our thoughts and prayers are with all of the friends, families and people affected by this unspeakable tragedy.

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1:30 p.m.

A law enforcement official confirmed to Milton that Mateen called 911 and declared his allegiance to ISIS. He identified himself to the 911 operator giving his full name, according to the source. He also mentioned the Tsarnaev brothers, the men who ignited explosives at the 2013 Boston Marathon.

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12:45 p.m.

Although some Twitter accounts linked to the terror group ISIS have describedMateen as a hero, the group has not claimed responsibility for the attack. Members of Congress have been told by authorities that Mateen appears to have made some sort of pledge of allegiance to ISIS, reports CBS News Correspondent Jeff Pegues.

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12:27 p.m.

A law enforcement source tells Milton that investigators are seeking search warrants for Mateen's residence, car, and communication devices, including his cell phone and computer. They are also seeking his financial and phone records to determine who Mateen has been in contact with, and in particular if he was communicating with anyone overseas.

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12:11 p.m.

Souces tell CBS News that suspect Mateen was on law enforcement radar during the last five years, but no formal investigation was opened. Mateen, who has worked previously as a security guard, was not under investigation at the time of the shooting.

A SWAT truck and a bomb disposal unit are on the scene of an address associated with Mateen, who is suspected of killing 50 and wounding 53, at a gay nightclub in Orlando early Sunday.

There is a media staging area set up about a block away from the apartment complex in a residential neighborhood in Fort Pierce, Florida, on Sunday.

Fort Pierce is about 118 miles southeast of Orlando. The apartment complex is a series of two-story buildings.

Numerous police officers and members of the FBI also area there.

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11:58 a.m.

CBS News has confirmed that the photo above is of Mateen, the man who authorities believe killed 50 and wounded 53 early Sunday, in a mass shooting at Pulse, a gay night club in Orlando.

Mateen's father says he is in shock and that he wasn't aware of anything his son might have been planning.

Mir Seddique, of Port St. Lucie, Florida told media that his son got angry when he saw two men kissing in Miami a couple of months ago and thinks that may be related to the shooting.

Seddique says: "We are saying we are apologizing for the whole incident. ... We are in shock like the whole country."

The father also says the incident has nothing to do with religion.

Officials say the shooter was among the 50 killed, and that they're investigating whether the incident was an act of terrorism.

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11:30 a.m.

The leaders of The American Muslim Community Centers, a mosque in Longwood, Florida, near Orlando, released a statement condemning the attack, which left 50 people dead and 53 injured early Sunday at Pulse a gay club, according to police.

"The American Muslim Community Centers is saddened and shocked by the senseless killings in downtown Orlando, and we pray for the victims and their family members," said Atif Fareed, the mosque's chairman. "AMCC and its members offer their deepest condolences to those affected by this tragedy, and we stand with our fellow Americans in this difficult time."

"Ramadan is a month of deep reflection and prayer. Senseless violence has no place in our religion or in our society. We strongly condemn this heinous act of violence against humanity," Fareed said.

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11:20 a.m.

Families and friends are awaiting word outside an Orlando hospital to learn whether their loved ones are among 50 killed and 53 more hospitalized at a shooting at a gay nightclub.

About 50 people were gathered outside Orlando Regional Medical Center on Sunday, many in tears and anxious.

Fatriana Evans frequents the Pulse nightclub and was outside when shots were fired.

Evans says, "It sounded like fireworks - pop, pop, pop - and then everybody scatters."

Jackie Smith was inside the club and says two friends next to her were shot. She says she hasn't gotten updates on their conditions. She came out of the hospital and burst into tears in the arms of friends.

She says: "Some guy walked in and started shooting everybody. He had an automatic rifle, so nobody stood a chance. I just tried to get out of there."

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11 a.m.

Police say the shooter at an Orlando nightclub used an AR-15-type assault rifle on all the victims.

Officials say 50 were killed at the popular gay club. That makes it the deadliest mass shooting in U.S. history.

Police Chief John Mina said at a Sunday news conference that the shooter used the assault rifle, with unknown rounds, and also had a handgun.

Officials at the news conference also say they have securing the suspect's vehicle, a van, right outside the club.

The shooter has been identified as Mateen of Port St. Lucie, Florida. Officials have said they're investigating whether the massacre was an act of terrorism.

Dr. Mike Cheatham is a trauma surgeon at Orlando Regional Medical Center, where 46 patients were taken. The majority are in critical condition.

He tells The Associated Press, "I think we will see the death toll rise."

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10:50 a.m.

The massacre at an Orlando nightclub that claimed 50 lives is the worst mass shooting in U.S. history.

Police Chief John Mina confirmed at a news conference Sunday morning that 50 people were killed, up from 20 as earlier reported.

Mayor Buddy Dyer says 53 more are hospitalized after the early Sunday incident. He says the shooter is among the dead. He also says the shooter used an assault rifle on all those dead. Officials say one officer was shot, and has injuries to his face.

Earlier, U.S. Rep. Alan Grayson identified the shooter as Mateen, of Port St. Lucie, Florida. He cited law enforcement officials in speaking to reporters.

Officials also have said they're investigating whether the incident was an act of terrorism.

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10:30 a.m.

The mayor of Orlando says there were 50 casualties and there are 53 more hospitalized after a mass shooting at a popular gay nightclub there.

"There's blood everywhere," Mayor Buddy Dyer said Sunday at a news conference, hours after the shooting.

He says the shooter used an assault rifle on all those killed.

Earlier, U.S. Rep. Alan Grayson identified the shooter as Mateen of Port St. Lucie, Florida. He cited law enforcement officials in speaking to reporters.

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10:20 a.m.

The suspect in the mass shooting at night club in Florida has been identified as Mateen of Port St. Lucie, Florida.

U.S. Rep. Alan Grayson identified the shooter in the Sunday incident. He cited law enforcement officials in speaking to reporters.

A federal law enforcement official with knowledge of the investigation also identified him. The official was not authorized to discuss the investigation publicly and spoke on condition of anonymity.

Florida Department of Law Enforcement Special Agent in Charge Danny Banks said earlier that the mass shooting is being investigated as an act of terrorism. He says authorities are looking into whether the incident was an act of domestic or international terror, and if the shooter was a lone wolf.

- Eric Tucker in Washington contributed.

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10:15 a.m.

Florida's governor is headed to Orlando after a shooting at a gay nightclub there left about 20 dead and 42 wounded.

Gov. Rick Scott says in a statement Sunday, hours after the incident, that thoughts and prayers are with the victims and their families.

The statement says he'll meet with law enforcement and local officials in Orlando.

Scott says: "We will devote every resource available to assist with the shooting in Orlando. Our state emergency operations center is also monitoring this tragic incident."

His statement also thanks the first responders.

Florida Department of Law Enforcement Special Agent in Charge Danny Banks said earlier that the mass shooting is being investigated as an act of terrorism. He says authorities are looking into whether the incident was an act of domestic or international terror, and if the shooter was a lone wolf.

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9:45 a.m.

President Barack Obama has been briefed by his homeland security and counterterrorism adviser about the shooting at a gay nightclub in Orlando that left about 20 people dead and 42 wounded.

The White House said Sunday, several hours after the incident, that Obama has been briefed and has asked for regular updates as the FBI and other federal officials work with Orlando police on the case.

Press secretary Josh Earnest said in a statement that the president has directed federal officials to provide "any necessary assistance to pursue the investigation and support the community."

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7:25 a.m.

Police say approximately 20 people have been killed inside a Florida nightclub, and at least 42 were wounded.

Orlando Police Chief John Mina says authorities have not determined an exact number of people killed, but that "approximately 20" have died.

Florida Department of Law Enforcement Special Agent in Charge Danny Banks says the mass shooting is being investigated as an act of terrorism. He says authorities are looking into whether the early Sunday incident was an act of domestic or international terror, and if the shooter was a lone wolf.

Mina says the shooter was armed with an assault-type rifle, a handgun and some type of suspicious device. Police had said previously on Twitter that there was a "controlled explosion" at the scene of the shooting at Pulse Orlando, a popular gay dance club. Mina says that noise was caused by a device intended to distract the shooter.

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7:15 a.m.

Police say multiple people have been killed inside a Florida nightclub, and at least 42 wounded people have been taken to hospitals.

Orlando Police Chief John Mina did not immediately provide an exact number of how many people were killed. Police had said previously that the shooting was a "mass casualty situation."

Mina says the shooter was armed with an assault-type rifle, a handgun and some type of device. Police had said previously on Twitter that there was a "controlled explosion" at the scene of the shooting at Pulse Orlando.

Mina also says the suspect had exchanged gunshots with an officer working at the club, then went back inside and took hostages around 2 a.m. About three hours later, a SWAT team made the decision to go inside and rescue the hostages. The shooter died in a gunfight with those officers.

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5:55 a.m.

Police say the person who opened fire inside a popular Florida nightclub is dead.

Orlando Police did not immediately provide further details on the department's official Twitter account on Sunday. It was not immediately clear how the shooter died. Police described the shooting as a "mass casualty situation" and said local, state and federal agencies were involved in the investigation.

It was not immediately clear how many people were wounded in the shooting, or if any of the victims had died. Police have told people to stay away from the area and said a noise in the vicinity was a "controlled explosion." No further details were provided on the explosion.

Dozens of emergency vehicles have swarmed the area around the club.

The club, Pulse Orlando, earlier posted on its own Facebook page just after 2 a.m.: "Everyone get out of pulse and keep running."

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5:15 a.m.

Police say a loud noise near the scene of a reported shooting at a nightclub in Florida was a "controlled explosion."

Orlando Police said on the department's official Twitter account Sunday that media should avoid "reporting inaccuracies." No further details were immediately provided about the explosion.

Police have said "multiple injuries" were reported following the incident at the Pulse Orlando nightclub near Orange and Kaley avenue. The department also advised people to stay away from area.

Multiple emergency vehicles have reportedly responded, including the Orlando Fire Department's bomb squad and hazardous material team.

Pulse Orlando earlier posted on its own Facebook page just after 2 a.m.: "Everyone get out of pulse and keep running."

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4:50 a.m.

Orlando Police say they are responding to a shooting at a nightclub in Florida.

A post on the department's official Twitter account early Sunday morning says "multiple injuries" have been reported following the incident at the Pulse Orlando nightclub near Orange and Kaley avenue. The department also advises people to stay away from area.

Multiple emergency vehicles have reportedly responded, including the Orlando Fire Department's bomb squad and hazardous material team.

Pulse Orlando earlier posted on its own Facebook page: "Everyone get out of pulse and keep running."

The incident follows the fatal shooting on Friday of 22-year-old singer Christina Grimmie, who was killed after her concert in Orlando by a 27-year-old Florida man who later killed himself. Grimmie was a YouTube sensation and former contestant on "The Voice."

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