Failed Execution in Oklahoma Generates Controversy Regarding the Death Penalty in the U.S. [Video]

The failed execution of an inmate in Oklahoma on Tuesday has unleashed once more a series of doubts on the death penalty in the U.S.

Clayton Lockett's execution, programmed for Tuesday, April 29, had to be stopped when a vein "exploded" unexpectedly, which forced authorities to stop the process and schedule it for later.

38-year-old Clayton Lockett died 43 minutes after receiving the lethal injection due to a massive heart attack, reported CNN.

According to the same source, Lockett seized uncontrollably after being administered the drugs, a cocktail which included a dose of midazolam which is supposed to make the inmated sentenced to death fall unconscious.

However, seven minutes after the drug was administered, Lockett was still conscious and even tried to rise and say "man" out loud, as he gasped, according to journalist Courtney Francisco of KFOR, a CNN affiliate.

The director of the state Department of Corrections, Robert Patton, told the media that Lockett's execution, programmed for 6:23 p.m. local time, had to be stopped since the drugs didn't seem to be having any effect, according to Reuters.

After a few minutes of agony, an official inside the execution chamber lowered the blinds to prevent those present to witness the execution from realizing what was happening.

"We believe a vein exploded and the drugs weren't working as intended. The director ordered the suspension of the execution," Jerry Massie, spokesman for the state Department of Corrections, told Reuters.

Due to what happened, Oklahoma's Governor, Mary Fallin, ordered an investigation to clear up what happened and emitted an order to delay executions in the state by two weeks, CNN quoted.

This is the most recent incident which raises doubts regarding the death penalty in the United States, since a strong debate on the protocol of the lethal drugs used in executions began last year.

Clayton Lockett was sentenced to death in 2000 for rape and murder of a 19-year-old in 1999.

Video via CNN.