Teen stabs college soccer player girlfriend in driveway after saying 'wait I have something for you' before his mother helps cover it up: Cops

A Pennsylvania teen and his mother are behind bars after he allegedly killed his girlfriend who was found dead in the back of a Jeep Cherokee — and then his mom helped cover his tracks.

Royce Moser, 18, is facing a charge of criminal homicide in the death of Karoline Heintz, who played soccer for PennWest California. Moser's mother, Rachel Moser, is charged with hindering apprehension and obstruction.

Pennsylvania State Police Trooper Rocco Gagliardi said at a press conference that cops conducted a welfare check on Heintz around 12:30 a.m. Thursday after her family hadn't heard from her.

Heintz's father told police that his daughter had left the family home at 9:30 p.m. and was likely heading to Target and then back to her dorm room at PennWest. The father said he checked his daughter's location, and her phone showed she had stopped at her boyfriend Royce Moser's home, according to a probable cause affidavit obtained by Law&Crime.

After about 30 minutes, Heintz appeared to be on the move again, police said. When her father could not get hold of her and told police, officers used an AirTag in her vehicle to locate her, the affidavit said.

Cops saw the Cherokee near a library in the tiny borough of California, which is about 40 miles south of Pittsburgh, and noticed some blood inside. They opened the hatch in the back of the car, where they found Heintz's body, Gagliardi stated.

A preliminary examination of the body showed a wound in Heintz's chest, the affidavit states. She also had fresh grass on various parts of her body and mouth, police said.

According to the probable cause affidavit, surveillance video showed a male who police say is Royce Moser driving Heintz's vehicle near where it was later located. The suspect appeared to be wearing blue latex gloves and was following another vehicle driven by a female who was also wearing latex gloves, police said.

Investigators later determined that woman was Royce Moser's mother, Rachel Moser.

Within 12 hours, police had the Mosers in custody.

When police spoke with Royce Moser, he allegedly told them Heintz had come over to his house around 10:15 p.m. on Wednesday and they talked while she sat in her vehicle in his driveway. He allegedly said at one point he got angry at something she had said to him, but "couldn't remember what."

Royce Moser told police he "then had the 'demon take over' him and tell him to stab Karoline." He told Heintz, "wait I have something for you," and went inside the residence to get a knife, police said.

He returned and stabbed her in the chest, the affidavit states.

Heintz fell out of the car and Royce Moser said he dragged her to the rear of the vehicle and put her in the back hatch and got in the driver's seat, according to the affidavit. He then allegedly called his mother for help moving the car.

When his mother arrived, she told him to pull the car into the garage and they would clean it with disinfectant, police said. She then reportedly gave him latex gloves and told him to follow her car.

In an interview with police, Rachel Moser allegedly said her son called in the early hours Thursday morning, saying he needed her to follow him to PennWest so he could drop off a vehicle.

While together on the way home after dropping Heintz's car off, Royce Moser allegedly admitted to his mother that he "stabbed the victim with a knife from his house." He then put Heintz's body in the back of the car, police said.

Royce Moser said to his mother he had "demons" who told him to hurt Heintz and he did not know if she was "dead or alive," the affidavit states.

When they got back to Rachel Moser's home, she told her son to "take a bath and then shower" and change his clothes, police said.

She put the knife in a garbage bag to be thrown out with the trash outside her home and washed his clothes.

Police later executed a search warrant at Rachel Moser's home and located a chef's knife in a garbage bag, according to the affidavit.

Heintz was a freshman on the PennWest soccer team. She graduated earlier this year from Peters Township High School, which is also in the Pittsburgh area.

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"PennWest University is deeply saddened by the tragic death of Karoline Heintz, who was a first-year student at the California campus," a statement from the university sent to local media said. "Our heartfelt condolences go out to her family, friends, and all those affected by this tragedy."

Royce Moser and Rachel Moser were being held at the Washington County Jail. Bond information and their next court date were not immediately listed.