It was not immediately clear whether the victims were wounded or killed. Police said at least two of them suffered gunshot wounds in yesterday's shooting.
The shooting took place on the campus of the Seattle Pacific University, the northwestern US city's police department said on its Twitter feed.
"Total of 4 victims found so far @scene of @SeattlePacific shooting. No info on conditions at this time. Police still searching campus," the police department tweeted.
KIRO TV said the two suspected gunmen were reported in separate buildings at the campus, citing witnesses as saying one came into a classroom and opened fire.