KANSAS CITY, Mo. – Kansas City Chiefs linebacker Jovan Belcher fatally shot his girlfriend 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 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 mid-morning and reporters were confined to the street just outside the gates.