OREGON CITY, Ore. — Police said Monday that they believe an 88-year-old man set fire to his house, shot a volunteer reserve police officer and then was killed by a SWAT team.The injured officer, 41-year-old Robert Libke of the Oregon City police department, died at a Portland hospital this afternoon after the confrontation on Sunday. A procession from Legacy Emanuel Medical Center to Lincoln Memorial Park Funeral Home is planned for 4 p.m. Police identified the suspected gunman as Lawrence Cambra, who was one of two residents of the burned home. A woman who also lives there was uninjured. Officials said they are still trying to determine a motive, but they don’t believe the fire was intentionally set to lure police into an ambush. The Oregonian reported that Cambra has a history of domestic disputes.Police and firefighters were dispatched to Cambra’s home on Sunday after reports that it was burning. The reports said a man on the scene had a handgun.