KANSAS CITY, Mo. — Kansas City Chiefs linebacker Jovan Belcher fatally shot his girlfriend on Saturday, then drove to Arrowhead Stadium and committed suicide in front of his coach and general manager.

Authorities did not release a possible motive for the murder-suicide, though police said that Belcher and his girlfriend, 22-year-old Kasandra M. Perkins, had been arguing recently. The two of them have an infant child.

Belcher thanked general manager Scott Pioli and coach Romeo Crennel before shooting himself in the parking lot of the team’s practice facility, police spokesman Darin Snapp said. Police had locked it down by midmorning and reporters were confined to the street just outside the gates.

The Chiefs will play the Carolina Panthers on Sunday at Arrowhead Stadium as scheduled after discussing it with the league, Crennel and the club’s captains. Crennel will coach the team.

Belcher was a 25-year-old native of West Babylon, N.Y., on Long Island, who played college ball at Maine. He signed with the Chiefs an undrafted free agent, made the team and stayed with it for four years, moving into the starting lineup. He’d played in all 11 games this season.

“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 a statement.

“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.”

Authorities reported receiving a call Saturday morning from a woman who said her daughter had been shot multiple times at a residence about five miles away from the Arrowhead complex. The call actually came from Belcher’s mother, who referred to the victim as her daughter, leading to some initial confusion, police said.

Chiefs linebacker Jovan Belcher fatally shot his girlfriend early Saturday, then drove to Arrowhead Stadium and committed suicide in front of his coach and general manager, according to police. Ed Zurga/Getty Images
Police then received a phone call from the Chiefs’ training facility.

“The description matched the suspect description from that other address. We kind of knew what we were dealing with,” Snapp said. The player was “holding a gun to his head” as he stood in front of the front doors of the practice facility.

“And there were Pioli and Crennel and another coach or employee was standing outside and appeared to be talking to him. It appeared they were talking to the suspect,” Snapp said. “The suspect began to walk in the opposite direction of the coaches and the officers and that’s when they heard the gunshot. It appears he took his own life.”

The coaches told police they never felt in any danger, Snapp said.

Linebackers coach Gary Gibbs was also outside when the shooting occurred, a team official told ESPN NFL Insider Adam Schefter.

“They said the player was actually thanking them for everything they’d done for him,” Snapp said. “They were just talking to him and he was thanking them and everything. That’s when he walked away and shot himself.”

Perkins was a cousin of Chiefs running back Jamaal Charles’s wife, Whitney, who introduced Perkins to Belcher.

Snapp said Belcher’s mother told police the couple had recently been arguing. A team source told ESPN that Belcher’s mother had come to Kansas City last week at the request of her son because the couple was having problems and he needed help taking care of the baby.

“Our thoughts and prayers are with the Chiefs and the families and friends of those who lost their lives in this terrible tragedy,” the NFL said in a news release. “We have connected the Chiefs with our national team of professional counselors to support both the team and the families of those affected. We will continue to provide assistance in any way that we can.”

Joe Linta, Belcher’s agent who also represents Crennel, said when he first heard the news, he thought it was a prank.

“He was the last person in the world you would expect,” Linta said. “Completely out of character for the guy I know. I didn’t have a lot of individual contact with him but this is so out of character for him. Completely out of character. He was charitable, polite, articulate — and something went crazy wrong.”

Linta said he hasn’t been in touch with Crennel since the incident.

“No I haven’t had a chance to speak to him,” Linta said. “I left a message saying I’m here for you. It’s one of those things where a lot have called, you’re in my prayers, but I’m just a piano player. There are a lot of people drastically impacted. It’s unbelievable to me.”

Some of the Chiefs reacted to the tragedy on Twitter.

“I am devastated by this mornings events,” Pro Bowl linebacker Tamba Hali wrote. “I want to send my thoughts and prayers out to everyone effected by this tragedy.”

A large group of Belcher’s friends and relatives gathered Saturday at his boyhood home on Long Island.

His family turned the front yard into a shrine, with a large poster of Belcher, an array of his trophies, and jerseys and jackets from Kansas City, Maine and West Babylon High.

“He was a good, good person … a family man. A loving guy,” said family friend Ruben Marshall, who said he coached Belcher in youth football. “You couldn’t be around a better person.”

Belcher is the latest among several players and NFL retirees to die from self-inflicted gunshot wounds in the past couple of years. The death of the beloved star Junior Seau, who shot himself in the chest in at his California home in May, sent shockwaves around the league.

Kansas City Mayor Sly James said he spoke to Pioli after the incident, and while he refused to discuss the GM’s emotional state, the mayor said Pioli was “extremely concerned that fans of this team are not disappointed and not left in the cold.”

“I think they think there’s an obligation to the people of this city, the fans of the team and the fans of the other team to play the game,” James said.

The Chiefs, once expected to contend for the AFC West title, are 1-10 and mired in an eight-game losing streak.

“The Oakland Raiders are empathizing with the Chiefs organization,” the Chiefs’ AFC West rivals said in a statement. “Our hearts are wounded by such an unimaginable tragedy in our NFL family.”

Belcher had started 44 of 59 games in his four seasons for the Chiefs, recording a career-high 61 tackles in 2011.

Raibonne Charles, a former Maine defensive lineman and teammate, said Belcher played the game with passion and was “a passionate person in life.”

Charles said he hadn’t talked to Belcher much since he made it to the NFL, but that everyone is obviously shocked.

“To be honest with you, I kind of just crumbled inside when I first heard the news,” Charles said.

Maine coach Jack Cosgrove said Jovan was a “tremendous student-athlete.”

“His move to the NFL was in keeping with his dreams,” Cosgrove said in a statement. “This is an indescribably horrible tragedy. At this difficult time, our thoughts and prayers are with Jovan, Kasandra and their families.”

Charles described Belcher as an undersized linebacker whose 40-yard dash time wasn’t exceptional. But he was an inspiration for a lot of guys at the school because he made it to the NFL despite his shortcomings, Charles said.

“The state of Maine tends to take a lot of pride in guys who may not necessarily be from the state but play for the University of Maine and make the NFL,” Charles said. “I was often asked about him. ‘Did you get to play with that guy Jovan?’ This is definitely going to be devastating to the whole state.”

Information from The Associated Press, ESPN NFL Insider Adam Schefter and ESPN.com senior writer Elizabeth Merrill was used in this report.