A school student who went on a shooting spree before killing himself wrote a series of chilling tweets in the months before he ran amok with a gun.
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 left a series of posts on Twitter before his attack which painted a picture of a teenager who was familiar with using weapons.