A gunman at a school in Colorado has shot and wounded two students before dying of an apparent self-inflicted gunshot wound.
The school, south of Denver, is just 13 kilometres east of Columbine High School where a mass shooting in 1999 left 14 students dead.
The gunman brought a shotgun to Arapahoe High School and was looking for a specific teacher when confronted by a classmate, Arapahoe County sheriff Grayson Robinson said.
The teacher left the school after learning he was sought, the BBC reports. Another student suffered a minor injury.
Heavily armed police trained in "active shooter" scenarios stormed the building, ordering students outside with their hands over their heads. Inside, they found another student who had apparently suffered a minor gunshot wound.
Authorities also found the student believed to be the gunman, dead from an apparent self-inflicted gunshot wound.
The student who confronted and was shot by the suspect was in serious condition and undergoing surgery in hospital, the sheriff said.
The drama occurred the day before the anniversary of the shooting in Newtown, Connecticut, in which 20 schoolchildren and six workers were killed at a primary school.