KANSAS CITY, Mo. (AP) — Police hope to deliver an investigative report to prosecutors Tuesday, detailing what caused Kansas City Chiefs linebacker Jovan Belcher to kill his girlfriend and then himself.

“They’re moving it along just like any other case. There’s a formal process it has to go through,” Kansas City police Sgt. Marisa Barnes said.

In an incident report released Monday, officers were called to the Kansas City home of Belcher, 25, and his girlfriend, 22-year-old Kasandra M. Perkins at about 7:50 a.m. Saturday. Police found Perkins on the floor of the master bathroom, and the report said she died from apparent gunshot wounds, but did not say how many times she had been shot.

Belcher then drove about five miles to Arrowhead Stadium. There, he was met by general manager Scott Pioli and coach Romeo Crennel, and Belcher thanked them for all they’d done for him.

The police report said that when officers arrived at Arrowhead about 8 a.m. and saw several people in the parking lot outside the entrance to the practice facility.

“As they approached, a subject later identified as Jovan Belcher, observed their presence and moved to an area behind a vehicle,” the report said. “From that position Belcher shot himself one time in the head.”

Belcher was taken to a hospital, where he died, according to the report.

Barnes said Monday that firearms found at the couple’s home were legally registered to Belcher. It is unknown how many guns were found.

Police spokesman Darin Snapp also said Monday that Belcher’s mother, who had been staying with the couple, was given temporary custody of the couple’s 3-month-old daughter, Zoey.

Snapp said it was unclear Monday if the grandmother and baby were still in the Kansas City area or if they had returned to Belcher’s home in West Babylon, N.Y.

Perkins originally was from Texas. Perkins’ friend Brianne York, 21, said Sunday that Perkins met Belcher through her cousin, who is married to Chiefs running back Jamaal Charles.

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