John William King — an avowed racist who orchestrated the murder of James Byrd Jr. in one of America's most gruesome hate crimes of the latter 20th century — was executed Wednesday in Texas, authorities said.

King, 44, was pronounced dead by lethal injection at the Texas State Penitentiary at Huntsville at 7:08 p.m., a corrections spokesman said.

Asked whether he had a final statement, King said, "No," and then wrote out a single-sentence statement reading: "capital punishment: Them without the capital get the punishment," the spokesman said.

Supreme Court Justice Samuel Alito denied a last-minute application for a stay of execution, which delayed the execution by about an hour.

King was the ringleader of a group that chained Byrd, 49, who was African American, to the back of a 1992 Ford pickup and dragged him to his death over nearly three miles in the woods outside Jasper, Texas, on June 7, 1998. The killers left Byrd's mangled body by a roadside.

Byrd's murder shocked the nation and put a harsh light on race relations in the small town on the Louisiana border.

King, who has never shied from his racist beliefs, had hateful tattoos on his body, including one with a black person hanging by a noose from a tree, Nazi symbols and the words "Aryan Pride."

"Today, we witnessed the peaceful and dignified execution of John King for the savage, brutal and inhumane murder of James on June the 7th of 1988, really a modern-day lynching," said Byrd's older sister, Clara Byrd Taylor.

"King showed no remorse then and showed no remorse tonight," she said. "This execution tonight was just punishment for his actions."

Ricky Jason wears a photograph of James Byrd Jr. outside the Texas Criminal Justice Department Huntsville Unit in September 2011. David J. Phillip / AP file

Louvon Byrd Harris, Byrd's younger sister, said King's death at the end of a syringe paled in comparison to the unspeakable terror and pain her brother felt as he was being killed.

"All they are going to do is go to sleep," she said earlier. "But half the things they did to James, all the suffering he had to go through, they still get an easy way out to me."

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King's appeals lawyers had argued that trial attorneys seriously erred by conceding his role in the murder and addressing only the penalty phase.

"From the time of indictment through his trial, Mr. King maintained his absolute innocence, claiming that he had left his co-defendants and Mr. Byrd sometime prior to his death and was not present at the scene of his murder," one of the lawyers, A. Richard Ellis, wrote in his petition to the Supreme Court.

"Mr. King repeatedly expressed to defense counsel that he wanted to present his innocence claim at trial," Ellis wrote.

King had also said that Byrd's death wasn't a hate-fueled murder but a drug deal gone awry.

King was the second man to be put to death in thecase following the execution of Lawrence Russell Brewer in 2011. The third person convicted of Byrd's murder, Shawn Allen Berry, was sentenced to life behind bars.

Billy Rowles, who led the investigation when he was sheriff of Jasper County, met with Brewer a week before he was put to death. Brewer confirmed that "the whole thing was Bill King's idea," Rowles said.

Rowles said he still couldn't fathom how Byrd's killers could have carried out such a barbaric act.

"The fact that a human being — a living, breathing human being — was jumped, beat, chain-wrapped around his legs and drug behind their truck for close to three miles, that is so far over my head that anyone could do something like that, let alone three of them, could do something like that," Rowles, now the sheriff of Newton County, told NBC Dallas last year.

"Drag that man until his body came apart, and untied the body, left it in the middle of the road so everybody could see, and drove off and went home and went to bed," he said.

The Texas Court of Criminal Appeals and the state's Board of Pardons and Paroles both rejected defense requests to delay or commute King's execution on Monday.

King is the fourth person to have been executed in the United States this year and the third in Texas, which has long been the nation's most active capital punishment state.