Oklahoma Inmate Execution Halted, Dies From Heart Attack

An execution surrounded by controversy went wrong Tuesday night at the state penitentiary, and a second execution was immediately canceled.

Convicted murderer Clayton Lockett is dead, but not from the new formula of drugs the state is using for the first time. Instead, Lockett died from a massive heart attack that occurred almost 40 minutes after the execution began.

Lockett was asked if he had any last words. He responded with a subtle no.

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The execution began, and 10 minutes later, he was officially announced unconscious. Then, the drugs that are supposed to stop respiration and the heart were injected. That's when Lockett began to mumble and slowly convulsed with his head and upper body lifting off the execution table.

The curtains were then lowered. Minutes later, Oklahoma Department of Corrections Director Robert Patton stopped the execution, citing a vein failure.

Later, Patton addressed the media.

"There was some concern at that time, that the drugs were not having the effect," stated Patton. "So the doctor observed the line, and determined that the line had blown."

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In other terms, the line blown means Lockett's vein burst.

Lockett's attorney said there is potential for a lawsuit.