A Ft. Carson soldier is behind bars accused of brutally murdering 19-Year-old Judilianna 'Judi' Lawrence.
Specialist Robert Marko was arrested Monday night on his 21st birthday.
He faces first degree murder and sexual assault charges.
According to court documents obtained by 11 News, Marko led detectives back to the crime scene on Monday. He told them after having intercourse with the victim, they got into an argument.
At that point, he allegedly blindfolded and gagged the victim before cutting her throat.
He is now being held without bond at the Criminal Justice Center.
"He's cooperating. We didn't get all good information. But, still at this point he is cooperative," said Lt. Lari Sevene with the El Paso County Sheriff's Office.
Family members say Lawrence met Marko online. Authorities say the two met up on Friday, the same day she vanished.
Her body was found late Monday afternoon on private property off of Old Stage Road.
Specialist Marko joined the Army in June of 2006 and was deployed to Iraq last year.
He is expected to make his first court appearance next Monday morning.