Texas Man Planned Police HQ Bloodbath Attacker ignited trailer full of explosives, opened fire yesterday By Rob Quinn, Newser Staff Posted Aug 18, 2010 4:09 AM CDT 18 comments Comments Patrick Gray Sharp is shown this undated hand out photo released by the Texas Department of Public Safety. (AP Photo/Texas Department of Public Safety) (Newser) – Police are trying to figure out the motive behind a Dallas-area man's massive assault on a police station with guns and explosives yesterday. Patrick Gray Sharp, 29, set fire to a trailer full of explosives outside McKinney police headquarters and then fired more than 100 rounds at the building. The explosives failed to detonate and nobody was hurt apart from Sharp, who was found dead from a bullet wound. Investigators aren't sure whether he killed himself or was shot by police officers returning fire. Police believe Sharp was trying to draw people out of the building so he could shoot them from a nearby field where he had set up a sniper position. "We know who, what, when, where, and how, but we don’t know why," McKinney police chief Doug Kowalski tells the Dallas Morning News. "There's no clear cut motive at this time." Sharp, who had no criminal record, quit his job at a local manufacturer a few days ago.