Police in the US state of Washington are trying to work out the motive behind a high school shooting there, which killed two people.

The gunman shot dead a classmate before turning the weapon on himself.

Four other people have been injured, three of them seriously.

Rick Smith - the police chief in Marysville where it happened - says it raises fresh questions about gun control in America.

Jaylen Fryberg opened fire in a cafeteria, murdering one and critically injuring three others at Marysville-Pilchuck High School in Marysville, about 35 miles north of Seattle, Washington.

A student who called himself Austin told an affiliate of CNN that the gunman was initially "quiet" before opening fire on fellow diners.

Austin said: "There was just a big group of kids... He was quiet. He was just sitting there. Everyone was talking. All of a sudden I see him stand up, pull something out of his pocket.

"At first I thought it was just someone making a really loud noise, like a bag, like a pretty loud pop, until I heard four more after that, and I saw three kids just fall from the table like they were falling to the ground dead."

Fryberg was crowned the school's freshman "homecoming prince" just a week ago, according to some US media.

The three in a critical condition were admitted to Providence Regional Medical Center in Everett.

Another patient, a young man in a serious condition, was sent to Harborview Medical Center in Seattle. Two of the wounded were male and two female, hospital officials said.

TV footage showed students being evacuated from the school, which has about 2,500 enrolled.

Another shooting occurred in the state in June at Seattle Pacific University, where a gunman killed a student and wounded two others.

Originally posted at 7:14am