Police did not release any additional information Sunday about the murder-suicide. Belcher shot 22-year-old Kasandra M. Perkins multiple times Saturday morning before driving about five miles to Arrowhead Stadium, thanking general manager Scott Pioli and coach Romeo Crennel for all they'd done for him. Belcher then fatally shot himself in the practice facility's parking lot.
Belcher and Perkins, who originally was from Texas, had a 3-month-old daughter.
On Sunday, a man who answered the door at the couple's home asked reporters, "Can you all respect grieving?" A short time later, at the same time the Chiefs were playing the Carolina Panthers, two men loaded bags into a car, and two women drove away.
Attempts to reach various members of Perkins' family in Austin, Texas, were unsuccessful.
Neighbors in the newly built Kansas City subdivision where the couple had lived since April were stunned by Saturday's violent events.
Kristen VanMeter, 31, lives near the couple and said she had taken community-college courses with Perkins.
"He was kind of quiet," she said of Belcher, with whom she would occasionally exchange pleasantries.
VanMeter said the couple threw "a lot of parties" but heard nothing unusual the morning of the killing.
"It's a surprise," she said. "There had to of been something that triggered it."
Kansas City police spokesman Darin Snapp reiterated Sunday that the couple had argued recently but could provide no additional details.
Belcher's mother, who recently had moved in with the couple, called 911 after her son shot Perkins. Snapp said 911 tapes aren't public records in Missouri.
He declined to discuss whether autopsies were being conducted.
Shawn Martin, vice president of the neighborhood homeowner's association, said she wasn't aware of any problems that preceded the shooting.
She described the parties at the home Belcher and Perkins shared as "nothing more than any other young couple" would have.
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