eddie routh
Former Marine Eddie Ray Routh enters the court after a break during his capital murder trial in Stephenville, Texas in this February 19, 2015 file photo. A jury found Roth guilty February 24, 2015 of murdering Chris Kyle, the former U.S. Navy SEAL whose autobiography was turned into the hit movie "American Sniper." Reuters/LM Otero/Pool/Files

Eddie Ray Routh murdered Navy SEAL sniper Chris Kyle and friend Chad Littlefield, a jury decided in a Stephenville, Texas, courtroom Tuesday. The verdict was announced at 10:20 p.m. EST, less than three hours after the defense and prosecution rested their cases, NBC News wrote. He was sentenced to life in prison without parole.

Routh murdered Kyle and Littlefield at a gun range on Rough Creek Lodge and Resort during what was supposed to be a therapeutic outing for Routh. Though the defense argued he was insane at the time of crime, the jury thought otherwise. Prosecutors did not ask for the death penalty.

In a new tape played in court Tuesday, the jury heard the admitted killer explain how he felt after Kyle and Littlefield were dead. "It tore my [expletive] heart out what I did. I don't know why I did it, but I did it,” Routh told the New Yorker magazine on May 31, 2013, four months after the incident, according to NBC News. "I feel so [expletive] about it," Routh said. "I guess you live and learn, you know."

The prosecution argued this was an admission of guilty, that Routh could not have been insane at the time of the murder, ABC News wrote. But defense attorney Warren St. John maintained Routh believed Kyle and Littlefield were going to kill him if he did not shoot them first. "He killed those men because he had a disillusion, he believed in his mind they were going to kill him," St. John said.

The case received wide attention after Kyle’s memoir, “American Sniper,” was turned into an Oscar-nominated film starring Oscar-nominated actor Bradley Cooper. Kyle claimed to be the deadliest sniper in American history with 160 confirmed kills in Iraq.

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