Convicted murderer Clayton Lockett was scheduled to be executed at 6:00 p.m. tonight (April 29). While authorities were administering the lethal injection they discovered the line into Lockett's arm had blown. Prison officials halted the execution and at 7:06 p.m. Lockett suffered a massive heart attack and passed away.

A second death row inmate, Charles Warner, was scheduled to be executed at 8:00 p.m. tonight. His execution has been delayed for 14 days due to the circumstances surrounding Lockett's botched execution.

Today would have been Oklahoma's first double execution since the late 1930s.

Clayton Lockett and Charles Warner have argued the state's secrecy over the combination of lethal drugs violates their constitution rights and could result in a cruel and unusual death. The Oklahoma Supreme Court eventually lifted a stay of execution and ruled the inmates' claims were "frivolous and not grounded in the law."

Clayton Lockett was found guilty of kidnapping, beating, raping and shooting a 19-year-old woman and then burying her alive. Charles Warner was found guilty of raping and killing an 11-month-old baby in 1997.

For more details on the case visit KFOR.com