Hours before a woman was found shot to death in a camper in Montrose County, a man walked into police headquarters in Olathe, "gasping for breath" and claimed he had shot his father, who he said was actually a transgender woman.

Joseph Anthony Saur, 19, walked into the Olathe Police Department just before midnight on Monday, Nov. 6 "visibly emotional and distraught," according to court documents.

Police say Saur told police he had shot and killed his father "in self-defense," but couldn't remember where he had done so.

Olathe Police Chief George Jackson began interviewing Saur, who said he shot his "real biological father" who "had a sex change" and was now a transgender woman named Patience Rian Stewart.

Saur's father, when contacted by police, said he was alive and well, and told police his son had recently started using methamphetamine again.

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Eventually, police were able to determine the location Joseph Saur was talking about - 205 West 4th Street in Olathe - a residence about four blocks from the police department.

When police arrived at the home, they saw a white truck camper on the ground in the yard near the main house.

Inside the camper was the body of 28-year-old Patience Stewart, discovered on a bloody mattress, holding a methamphetamine pipe in one hand and a lighter in the other, according to police.

Police said Stewart was shot multiple times.

Saur told Olathe Police that his father underwent a sex change operation to "keep from getting caught," but couldn't provide any coherent details on why or how he knew this, according to his arrest affidavit.

He told police he shot Patience in self-defense after a scuffle inside the camper over a gun, which had perhaps been stolen from a pawn shop in Montrose.

Evidence inside the camper, detailed in an arrest affidavit from Olathe Police, did not indicate there had been a scuffle.

Saur also pointed out to police the location on the side of the road at South Church Street and 5th Street in Olathe where he said he had tossed the weapon, a 9mm handgun, according to the affidavit.

Saur was arrested and booked into jail on first-degree murder charges.

About an hour before Saur walked into the Olathe Police Department, local dispatch reported a 911 call from a man who said "someone was walking on his camper rooftop" in the area where Stewart's body was eventually discovered. The caller said he thought there was "a shooter on his roof" and then hung up.

When asked for more information, the caller hung up, police reported.

An Olathe Police Officer was dispatched and did not see anyone walking in the area so cleared the scene at 10:48 p.m., according to a police report.