Al Thunder recalls going to a basketball game at Red Lake High School on the Ojibwa Indian reservation in northern Minnesota. He couldn't help noticing another of the spectators, a tall, husky kid dressed in a black trench coat and boots, all adorned with chains. It was Jeff Weise, 16, who was known—and was often taunted—around the school for his menacing attire and antisocial ways. "He was a Goth," says Thunder, 75. "He was kind of a loner."

On the afternoon of March 21, Weise's alienation, authorities say, suddenly turned murderous. He first went to the home of his grandfather Daryl Lussier, 58, a tribal police officer, and killed him and his girlfriend. Donning his grandfather's bulletproof vest and strapping on his gun, he stole his squad car and drove it to the high school. After killing an unarmed security guard at the entrance, he went on a 10-minute rampage in the school, carrying a shotgun and shooting at anyone he saw. "You could hear a girl saying, 'No, Jeff, quit, quit. Leave me alone,' " student Sondra Hegstrom told the Bemidji Pioneer. When it was over, five students and one teacher were dead and seven people were wounded. Dead as well was Weise, who apparently turned a gun on himself as police stormed through the halls. "My wife and I didn't sleep a wink last night," says Francis Brun Sr., 70, father of slain guard Derrick Brun, 28. "I would wake up with uncontrollable sobbing."

It was the worst U.S. school shooting since Columbine in 1999, which claimed the lives of 12 students and one teacher. But according to former FBI profiler Clint Van Zandt, the lessons of that earlier tragedy, when police waited precious minutes for SWAT teams to arrive, had not been forgotten. "There are people alive in Red Lake," says Van Zandt, "who wouldn't be alive if those officers hadn't gone right in."

There was no clear motive for Weise's bloody foray. According to family members, his father committed suicide about four years ago; his mother suffered severe brain injuries in a car accident. In postings, evidently by him, on an Internet bulletin board popular with neo-Nazis, he mentioned being investigated last year by school authorities for threatening an attack on his school. He said he had been cleared but added that no one should doubt his determination. "Once I commit myself to something," Weise said in what could be read as his awful epitaph, "I stay to the end."

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