Jovan Belcher snapped after arguing with his girlfriend about the paternity of their daughter, according to a New York tabloid.
But Kansas City police are denying the claim.
Belcher's mother, Cheryl Shepherd, told investigators that her son argued with Kasandra Perkins over the paternity of Zoey Belcher before he shot Perkins, according to a report from the New York Post.
After shooting Perkins nine times, Belcher went to Arrowhead Stadium where he took his own life just after 8 a.m. Dec. 1.
"The mother believed that there was an issue over whether (Belcher) was the father," a source close to the Chiefs told the Post. "She said he (believed he) wasn't necessary the father of the child."
The tabloid said a Kansas City law enforcement source confirmed this information, saying Shepherd told police that "there was question about the paternity."
But one of the detectives on the case and other Kansas City police sources told KCTV5 Friday that neither Shepherd nor anyone else has raised the paternity issue and the tabloid's report is inaccurate.
Kansas City Police Department spokesman Darin Snapp said he spoke with the lead detective and that he said that at no point did Shepherd or any family members say there was a question about paternity and that triggered the shooting.
"We have not one thing that says this is true," Snapp said in an e-mail Friday afternoon.
Shepherd was inside the home when the shots were fired. The 911 call released by the city showed that Shepherd was frantic with grief as she pleaded with dispatchers to get medical aid to Perkins, who she referred to as her daughter.
"Stay with me," Shepherd screamed as she repeatedly exhorted dispatchers to get an ambulance to her son's home as quickly as possible to help"Kasi."
"The ambulance is on the way! You hear me? You hear me! Kasandra! Stay with me!" she said.
Belcher's mother said Kasandra Perkins was barely conscious but seemed to be hearing what she was saying. The couple had argued in their bedroom when Belcher fired up to nine bullets into her body.
After hearing the shots, Belcher's mother raced into the room where she saw her son kiss his girlfriend on her forehead and apologize. The Chiefs linebacker kissed his daughter before fleeing the scene in his Bentley.
Belcher had come home about 6:30 a.m. after being at another woman's Midtown apartment. Perkins had come home about 1 a.m. after being at the Power and Light District in downtown Kansas City.
The Chiefs and Perkins' family have set up separate trusts for Zoey Belcher. In addition, the girl, who was born Sept. 11, will receive more than $1 million.
The baby's paternity is not part of the Kansas City Police Department's investigation.
"That would not be something they're going to investigate," Sgt. Marisa Barnes told the New York Post. "It's a 'he-said, she-said,' so there's no way to investigate. It would be nothing more than a civil matter."
Belcher and Perkins began dating in 2010. Perkins was the cousin of Whitney Charles who introduced the two. Whitney Charles is married to Chiefs running back Jamaal Charles.
Perkins had moved out of the east Kansas City home for a time and lived with the Charles', but she returned to living with Belcher by Thanksgiving.
Belcher's mother has temporary custody of the baby, but a permanent guardian has not been named.
Perkins family in a statement issued last week that may have alluded to the paternity rumors.
"There has been a disheartening amount of rumors and speculation surrounding the tragic loss of our Kasi. No one will ever truly know why this happened nor is there anything to be said that could justify or ease our pain. We miss her deeply and would like to shed light on the person she really was," according to the statement.
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