CODY, Wyo. (AP) — A man who was arrested in northwest Wyoming after police say he confessed to killing his girlfriend in their suburban Denver apartment is contesting extradition back to Colorado.

The Cody Enterprise reports 22-year-old Jonathan Akin has been charged with murder in the death of Autumn Rivera in Thornton, Colorado.

Authorities say Akin surrendered to police in Powell, Wyoming, last week, and officers found Rivera's body in the trunk of his car.

According to an arrest warrant, Akin told authorities he killed Rivera, but he did not remember how because he had "blacked out." Akin then drove to Wyoming and spent the night at his mother's house in Deaver.

Akin has an extradition review hearing scheduled for Friday in Park County.