KANSAS CITY, Mo. (AP/CBS St. Louis) – Kansas City Chiefs linebacker Jovan Belcher reportedly kissed his girlfriend on the forehead after killing her.

The Kansas City Star reports Belcher’s mother, who heard the gunfire from another room, rushed into the room and witnessed his final goodbye. He then reportedly apologized to her and also gave a kiss to his 3-month-old daughter before leaving.

The Kansas City Star learned those details and others from multiple police sources Monday as officers continued their investigation into why Belcher, 25, killed his live-in girlfriend, Kasandra Perkins, 22, on Saturday morning.

Arguments over relationship and financial issues had simmered for months between them, according to the sources cited by the Star. After fatally shooting Perkins, Belcher drove to the Chiefs’ Arrowhead Stadium parking lot and shot himself in the head as general manager Scott Pioli and head coach Romeo Crennel tried to stop him.

Police Sgt. Richard Sharp told The Kansas City Star that the couple had been arguing over relationship and financial issues for months and that the team had been “bending over backward” trying to help them. Sharp didn’t specify how long the couple had been undergoing counseling.

When Belcher arrived at Arrowhead on Saturday, he encountered Pioli in the parking lot and told him the assistance the team had offered hadn’t fixed the couple’s problems and now “it was too late,” Sharp said.

Belcher thanked the men for everything the team had done for him and asked if Pioli and team owner Clark Hunt would take care of his daughter, the Star reported.

Pioli tried to persuade Belcher to put down his gun as Crennel and linebackers coach Gary Gibbs arrived at the scene.

After that, Belcher reportedly said, “Guys, I have to do this.”

“I was trying to get him to understand that life is not over,” Crennel said Monday. “He still has a chance and let’s get this worked out.”

When Belcher heard police sirens approaching, he knelt behind a vehicle and shot himself in the head.

Investigators believe Belcher killed himself because he was distraught over shooting Perkins, Sharp said.

“He cared about her,” Sharp said. “I don’t think he could live with himself.”

The night before the killings, Perkins had attended a concert downtown with friends and Belcher had been out at the Power and Light District, police said, while Belcher’s mother was watching their 3-month-old baby. Detectives don’t know exactly what the couple was arguing about but Belcher was upset that Perkins had stayed out so late.

Autopsies with toxicology tests were performed on both bodies but it could be weeks before results are known, police said.

Police spokesman Darin Snapp said Monday that Belcher’s mother was given temporary custody of the couple’s daughter.

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