Why did he do it? Accused killer's neighbors left to wonder

Officers in an armored vehicle head toward the scene of standoff at an underground bunker in the woods in North Bend, Wash., on Friday, April 27, 2012. Law officers hunting for Peter Keller, an armed survivalist suspected of killing his wife and daughter, maintained a perimeter early Saturday around an elaborate, underground bunker where he might be hiding in the woods of Washington state. Authorities pumped tear gas into the structure after locating it Friday in the Cascade foothills. (AP Photo/seattlepi.com, Joshua Trujillo) MAGS OUT; NO SALES; SEATTLE TIMES OUT; TV OUT; MANDATORY CREDIT