LOS ANGELES (AFP) - One person was killed and three injured in a shooting at a Seattle college campus on Thursday, a hospital spokeswoman said.

Those injured, including one critically, were being treated at the Harborview Medical Centre after the shooting at Seattle Pacific University, the spokeswoman told local KIRO 7 television.

Seattle Police Department spokesman Chris Fowler meanwhile described how the young male gunman was taken into custody after opening fire in the lobby of a building on the campus.

After shooting three victims with a shotgun, he began to reload his gun when a student who was monitoring the building "confronted the shooter (and) was able to subdue the individual," Fowler told reporters, without directly confirming the one death.

"Once on the ground, other students jumped on top of them and they were able to pin the shooter to the ground until police arrived."

The shooting came less than two weeks after a mentally unstable 22-year-old opened fire at a campus in Santa Barbara, California, killing six people before turning the gun on himself.

School shootings have become a tragic periodic occurrence in the United States in recent years.

They include the December 2012 massacre in Newtown, Connecticut that left 20 small children dead, and the Virginia Tech college shooting in April 2007 in which 33 people died, including the lone gunman.