Christopher Leroy Collings was executed in Missouri on Tuesday for the rape and murder of a 9-year-old girl.

Collings, 49, died by lethal injection at 6:10 p.m. CST at the Potosi Correctional Center in Bonne Terre.

“Right or wrong I accept this situation for what it is,” Collings said in a written final statement. “To anyone that I have hurt in this life I am sorry. I hope that you are able to get closure and move on.”

Collings is the 23rd inmate to be executed in the U.S. this year and the fourth in the state of Missouri.

The U.S. Supreme Court declined to grant a stay of execution on Monday.

“Mr. Collings has received every protection afforded by the Missouri and United States Constitutions, and Mr. Collings’ conviction and sentence remain for his horrendous and callous crime,” Governor Michael Parson said in a statement on Monday. “The State of Missouri will carry out Mr. Collings’ sentence according to the Court’s order and deliver justice.”

In 2007, Collings kidnapped Rowan Ford, the 9-year-old stepdaughter of one of his friends, according to court records. He was found guilty of raping the child and strangling her with chicken wire.

Collings has said that he did not intend to kill Ford, but he panicked when she recognized him. He had lived with her family for several months that year.

Ford’s body was found in a cave about a week after her disappearance. An autopsy ruled that she died due to strangulation.

Ford’s stepfather, David Wesley Spears, was also charged with rape and murder related to the incident. He had confessed to sexually assaulting and killing Ford, but Collings denied his involvement.

Prosecutors withdrew the murder charge in 2012.

Spears accepted a plea deal, agreeing to plead guilty to endangering the welfare of a child and hindrance of prosecution. He was sentenced to 11 years in prison and released in 2015.

“I am so proud of the girl that she was turning out to be,” Rowan’s older sister, Ariane Macks, Ford’s sister, told USA TODAY. “A part of me died when my sister died. I did lose my ray of sunshine.”

Macks said Collings deserved to be sentenced to death for killing Ford.

“I wanted him dead, I still do…but they could have done something better than lethal injection because he’s going out easy,” she said. “I cannot even imagine the pain when [Rowan] was strangled. Chris being so tall and so big [compared] to my little sister, she didn’t have a fighting chance.”

In Colling’s clemency petition, his attorneys said he suffered from a brain abnormality that caused “functional deficits in awareness, judgment and deliberation, comportment, appropriate social inhibition, and emotional regulation” and he experienced abuse as a child. Parson denied the petition.

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