Two death-row prisoners have been executed, the first since the botched lethal injection of Oklahoma prisoner Clayton Lockett on April 29.

Lockett died of a heart attack 43 minutes after the drugs meant to kill him failed to work due to a collapsed vein and his execution was halted; witnesses say he was writhing on the table and appeared to be in pain during the procedure.

The practice has since faced a fresh wave of criticism, with many calling for Washington to put an end to capital punishment. However, Georgia inmate Marcus Wellons was pronounced dead at 11:56pm last night after receiving the lethal injection.

Wellons reportedly apologised to the family of India Roberts, the 15-year-old girl he was convicted of raping and murdering in 1989, ahead of his execution, saying "I ask and hope they will find peace in my death".

His final words were "I'm going home to be with Jesus," and he is said to have "hummed a prayer" as his death warrant was read out. An officer overseeing the procedure reportedly fainted just three minutes before Wellons was declared dead.

Only several minutes after Wellon's execution, another inmate – John E Winfield, convicted of double murder in 1996 – was also given the lethal injection, and was pronounced dead at 12.10am.

A third death-row prisoner, John Ruthell Henry, is to be executed tonight in Florida at 6pm, despite claims that he is mentally disabled which would disqualify him from receiving the death penalty.

Leader of the New Monasticism movement Shane Claiborne is an outspoken staunch opponent of capital punishment, and has condemned legalised executions as "traumatic" and a way by which to "glorify death".

In a recent blog post for RedLetterChristians.org, Claiborne insisted that all Christians "should be people who are consistently pro-life, pro-grace and anti-death".

"We dare not forget the story – of a God who so loved the world that Jesus was sent, not to condemn the world but to save it," he added.

His latest blog, written ahead of last night's executions, furthers this criticism and notes that there is growing support for his viewpoint across the US.

"It's not just liberals anymore, but all sorts of reasonable people (including conservatives and faith leaders) who are convinced that we can do better than this as a country...and we must," Claiborne writes.

One such conservative is Rev Jeff Hood, a Southern Baptist pastor and spiritual advisor to death row inmates who Claiborne notes is "deeply troubled by his denomination's stance on capital punishment".

As a citizen of Texas, a state responsible for 37 per cent of all executions in the US – 515 since the reinstatement of the death penalty in 1976 – Hood feels compelled to stand against legalised executions.

"The death penalty makes us both killers and victims. Only love can heal us," he says.

Hood is thus embarking upon a 200 mile walk through the desert in Texas, being hosted by church groups along the way and speaking to people about his convictions.

"He [Jeff] is haunted by the way Christianity has been misrepresented when it comes to execution," Claiborne writes, adding that a cross sits on top of the Huntsville Unit, which houses the state of Texas' execution chamber.

"It's a contradiction that not enough Christians recognise – Jesus was a victim of the death penalty, not a proponent of it. Jeff described his hope that is more and more Christians embraced Jesus' life and teaching we would end the death penalty in America, for its strongest pillars are in the heart of the Bible belt.

"He is hopeful, and so am I," Claiborne finishes.

"The Gospel is good news. The merciful will be shown mercy. March on, brother Jeff. I hope with every step you take, every mile you walk, we get a little closer to the abolition of the death penalty in Texas, in the USA, and in the world.

"March on, brother, march on to the promised land."