KANSAS CITY, Mo. (AP) — It began like any other Saturday for the Kansas City Chiefs during the NFL season, their general manager and coach at work early to put final touches on this weekend’s game plan. Then they got a call to hurry to the parking lot.

The two men rushed through the glass doors of Chiefs headquarters and came face-to-face with linebacker Jovan Belcher, holding a handgun to his head.

Belcher had already killed his girlfriend and sped the short distance to Arrowhead Stadium, right past a security checkpoint guarding the entrance. Upon finding his bosses, Belcher thanked general manager Scott Pioli and head coach Romeo Crennel for giving him a chance in the NFL. Then he turned away and pulled the trigger.

The murder-suicide shocked a franchise that has been dealing with controversies now made trivial by comparison: eight consecutive losses, injuries too numerous to count, discontent among fans and the prospect that Pioli and Crennel could be fired at season’s end.

• Related: Belcher dead in apparent murder-suicide
• Related: Chiefs owner talks about decision to let team play on Sunday

Authorities did not release a possible motive while piecing together the case, other than to note that Belcher and his girlfriend, 22-year-old Kasandra M. Perkins, had been arguing frequently.

The two of them left behind a 3-month-old girl. She was being cared for by family.

The Chiefs issued a statement that said their game Sunday afternoon against the Carolina Panthers would go on as scheduled, even as the franchise tried to come to grips with the awfulness of Belcher’s death.

“The entire Chiefs family is deeply saddened by today’s events, and our collective hearts are heavy with sympathy, thoughts and prayers for the families and friends affected by this unthinkable tragedy,” Chiefs chairman Clark Hunt said in brief a statement.

A spokesman for the team told The Associated Press that Crennel plans to coach on Sunday.

“I can tell you that you have absolutely no idea what it’s like to see someone kill themselves,” said Kansas City Mayor Sly James, who spoke to Pioli shortly after the shootings.

“You can take your worst nightmare and put someone you know and love in that situation, and give them a gun and stand three feet away and watch them kill themselves. That’s what it’s like,” James said. “It’s unfathomable.”

Chiefs quarterback Brady Quinn told The Kansas City Star that when the team met later Saturday morning, Crennel broke the news to them.

“It was obviously tough for coach to have to tell us that,” Quinn said. “He really wasn’t able to finish talking to us. We got together and prayed and then we moved on.”

But Quinn said the team was so stunned, it was hard to digest what had happened.

“It’s hard mostly because I keep thinking about what I could have done to stop this,” he said. “I think everyone is wondering whether we would have done something to prevent this from happening.”

The 25-year-old Belcher was from West Babylon, N.Y., and played college football at Maine. He signed with the Chiefs as an undrafted free agent, made the team and hung around the past four years, eventually moving into the starting lineup. He played in all 11 games this season.

The NFL released a statement expressing sympathy and pledging “to provide assistance in any way that we can.” The players’ association has also been in touch with members of the Chiefs.

“We sincerely appreciate the expressions of sympathy and support we have received from so many in the Kansas City and NFL communities, and ask for continued prayers for the loved ones of those impacted,” Hunt said. “We will continue to fully cooperate with the authorities and work to ensure that the appropriate counseling resources are available to all members of the organization.”