A man who admitted to killing a Buckeye teen has been sentenced to 22 years in prison.
Robert Duffell was sentenced in Phoenix courtroom on Friday. In addition to prison he will face seven years of probation for murder and burglary.
The Maricopa County Sheriff's Office said in December 2014 Duffell, 17 years old at the time, admitted to killing 15-year-old Leah Costa, whose body was discovered in the desert.
Costa was reported missing by her mother on Christmas Eve and said to have run away with her boyfriend. On Saturday, Dec. 27, Duffell was found walking along Interstate 10 near milepost 78.
He was disoriented, dehydrated, had torn clothing and could not tell police where Costa was located.
Authorities found what is believed to be the girl's body in the desert near the Saddle Mountain Recreational Area in Tonopah. The area is south of the I-10 near 411th Avenue.
Authorities said Costa suffered a gunshot wound to the head.
He reportedly told Department of Public Safety officers that Costa had been with him and was last seen at the TA Truck Stop at 339th Avenue along the I-10. They were also together at the Burnt Wells Rest Area near milepost 71, but he did not know where she was when he was contacted or exactly where they had been.