US | Wisconsin Teen Hostage-Taker Dies in Wisconsin Motive still a mystery; teacher hailed as hero By John Johnson Posted Nov 30, 2010 4:44 PM CST Copied A police vehicle blocks the driveway to Marinette High School Tuesday morning. (AP Photo/Mike Roemer) The 15-year-old who held classmates and a teacher hostage in Wisconsin yesterday died today of his self-inflicted gunshot wound. Samuel Hengel had nothing in his history to explain what happened, say police and those who knew him. “Not one hint that anything like this would happen,” a teacher at Marinette High School who's also a neighbor of the Hengels tells the Green Bay Press Gazette. “It’s so unexplainable.” Meanwhile, the local police chief is calling teacher Valerie Burd "nothing short of heroic," reports the Milwaukee Journal Sentinel. "She kept a very cool head and kept the suspect as calm as possible." Hengel refused to speak directly with police during the 5-hour standoff, but he allowed Burd to communicate via phone. “We may never truly know why this happened,” said the district attorney. Read These Next Iran's new leader issued a defiant first statement. Country star cancels rest of his tour: 'I am mentally unwell.' Report finds uninjured cop took an ambulance as a dying man waited. Second 'Doomsday Plane' in 2 months is seen over California. Report an error