Thornton, Colo. — A Thornton man who was arrested in northwest Wyoming after police say he confessed to killing his girlfriend in Thornton and then driving her body across state lines will be extradited back to Colorado to face a felony murder charge.

Jonathan Akin, 22, is accused of killing his girlfriend Autumn Rivera on Nov. 25.

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According to an arrest affidavit, Akin and Rivera had gone out clubbing on Nov. 24. They took an Uber home early the next morning, and Rivera texted her sister that she and Akin were fighting about their relationship, the affidavit says.

The affidavit says Akin claims he was cutting up fruit to help with his hangover while Rivera was in the shower. He said Rivera was yelling at him. According to the affidavit, Akin said he blacked out and when he woke back up Rivera was dead.

Akin then drove over to his mother's house, according to the affidavit, and spent the night there. The next morning, Nov. 26, he told his mother he had killed Rivera but didn't know what had happened.

According to the affidavit, Akin then put Rivera's body in the trunk of his car and drove to Wyoming.

On the morning of Nov. 27, Rivera's sister attempted to contact Akin, the affidavit says, because she had not heard from Rivera and she knew Rivera had missed work. According to the affidavit, Rivera's sister said Akin called her back that morning and admitted that he had killed Rivera and was going to turn himself in.

The affidavit also says Akin spoke on the phone to a man he had lived with as a child on the morning of Nov. 27. That man said Akin was crying and hysterical and said that Rivera and Akin pushed each other during a fight before Akin "lost it" or "flipped out."

Akin turned himself in to police in Powell, Wyoming on Nov. 27.

He told police at that time he had found Rivera dead that morning but could not remember what had happened because the couple had drank a lot of alcohol, according to the affidavit. Akin also told detectives Rivera's body was in the trunk of his car.

Detectives found Rivera's body, wrapped in a bedsheet.

Akin was arrested and is currently being held in the Park County Detention Facility in Cody, Wyoming.

Following Friday's extradition hearing, Akin will be sent back to Colorado to face a charge of first-degree murder. Thornton Police have not released when that will happen.

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