ADAMS COUNTY, Colo. -- An arrest has been made in connection with the homicide of 19-year-old Natalie Bollinger, the Adams County Sheriff's Office said Thursday night.
Joseph Michael Lopez, 22, was arrested in connection with the case. He was in the Adams County Detention Center Friday.
Adams County Sheriff Michael McIntosh said Lopez and Bollinger knew each other through social media and had been friends for a short period of time. Investigators did not know the motive for the killing.
Lopez came to the sheriff's office on his own, answered questions and was arrested Thursday night, He was booked for first degree murder, the sheriff said.
An autopsy conducted by the Adams County coroner said Bollinger died from a gunshot wound to the head. The report also said she had a history of heroin and methamphetamine use. The report said at the time of her death, she had a "potentially lethal level of heroin in the blood."
Bollinger's body was found along a dirt road by a passerby on Dec. 29 in Adams County.
Since then, investigators have not said much about her death or a possible suspect.
Investigators have said her death was being investigated as a homicide.
Bollinger left her home after speaking to a family member and had not been seen since, the Broomfield Police Department said.
She had a protection order in place against a 42-year-old man weeks before she went missing.
Investigators have said they've had a person of interest in the case who was in custody on unrelated charges.
No court date has been set for Lopez.