A student opened fire Friday inside his high school cafeteria near Seattle, Washington, killing a fellow student and wounding four others before killing himself.
Police said three of the wounded were in critical condition at a nearby hospital. They said they were confident that only one shooter was involved.
The attack occurred at Marysville-Pilchuck High School in Marysville, about 55 kilometers north of Seattle.
Television pictures showed people streaming out of the school with their hands over their heads as armed officers ran by.
Police have not released the shooter's identity, but witnesses said he was a freshman and a popular student. There was no word on a motive.