Though motive has not been established, the UPS driver who opened fire during a meeting with co-workers had filed a grievance that he was working excessive overtime and appeared to specifically go after the three drivers he killed before fatally shooting himself. Jimmy Lam, 38, filed the grievance in March complaining of too much overtime and requesting that the package delivery company relieve him of working extra hours going forward, Joseph Cilia, an official with a Teamsters Union local that represents UPS workers in San Francisco, tells the AP. During a Wednesday morning meeting, Lam walked up to driver Benson Louie and shot him. As his co-workers frantically fled the room, he shot Wayne Chan in the back, and then walked up to him and "finished him."
Mike Lefiti was fleeing the building when Lam went out onto the street and shot him, Cilia says witnesses told him. "It's senseless. I can't think of anything. Why him? Why them?" Cilia asked. "I can't put it together." Officials late Wednesday confirmed San Francisco residents Louie, 50, and Chan, 56, and 46-year-old Lefiti, of Hercules, were killed in the shooting. Two other UPS employees were wounded, but Cilia says both were released from the hospital. As for Lam, "the suspect put the gun to his head and discharged the weapon," says Assistant Police Chief Toney Chaplin, adding that police did not fire any shots. Two guns were recovered at the scene, and SFGate reports one was an assault pistol. It adds that police towed a 2012 BMW from the scene and removed a computer and other potential evidence from Lam's home.