A high school student has shot dead nine people and then killed himself in the worst school shooting in the United States since the 1999 Columbine massacre.
Among the dead at Red Lake High School on Minnesota's Red Lake Indian Reservation were a male security guard, a female teacher, and at least six students including the gunman. At least a dozen others were wounded.
Jeff Weise, 15, who openly admired Adolf Hitler and had been questioned before about threats at his Minnesota school, killed himself after exchanging gunfire with police.
Before arriving at the school, Weise shot dead his grandfather, identified as veteran tribal police officer Daryl "Dash" Lussier, and Mr Lussier's girlfriend at their home in Red Lake village.
"We believe the shooter was acting alone," FBI agent Paul McCabe said, adding the dead at the school were all in one room.
One victim was identified by a friend as teacher Neva Rogers (62), the Minneapolis Star-Tribunenewspaper reported.
The gunman fired at doors of classrooms barricaded by terrified students and teachers, witnesses said.
"He came into the school and the first person he shot was the security officer at the door," said Molly Miron, editor of the Bemidji Pioneernewspaper. "One of the students told me he pointed his gun at a boy and then changed his mind, smiled, waved at him, and shot somebody else."
Police, alerted to the massacre when students used mobile phones to call for help, said they exchanged gunfire with the gunman who ducked into a classroom and shot himself.
Witnesses said he was armed with a shotgun or rifle and at least one handgun.
The gunman's motive was not immediately known, the FBI said, though a classmate told a local television station that he had spoken a year ago of wanting to "shoot up the school".
Relatives said Weise was a loner who usually wore black and was teased by
other kids.
They said his father committed suicide four years ago, and his mother was nursing home after suffering brain injuries in a car accident.
Jeff Weise admired German dictator Adolf Hitler and was a suspect following threats made at his school last year, he revealed in an internet forum frequented by neo-Nazis.
"I guess I've always carried a natural admiration for Hitler and his ideals,
and his courage to take on larger nations," Weise wrote on the website.
He said he was interested in finding like-minded Indians, a goal other
messages on the website encouraged.
He also admitted he was a suspect in a threat at school.
It was the deadliest US school shooting since the April 20th, 1999, Columbine High School massacre in Colorado in which 14 students - including the two killers - and a teacher died.
The Minnesota reservation 100 kilometres south of the Canadian border is controlled by the Ojibwa tribe, commonly known as the Chippewa, which has roughly 10,000 members, about half of whom live on the reservation.