DEKALB, Ill. - A former graduate student armed with two handguns and a shotgun opened fire Thursday in a large lecture hall on the campus of Northern Illinois University, killing five students and wounding 16 others before killing himself, authorities said.

University President John G. Peters said six students — four women, the shooter and another man — were killed in what he described as a “very brief, rapid-fire assault.” Sixteen other students were injured by gunfire or flying glass, authorities said.