The armed Fairfield, Conn., man who prompted a lockdown Tuesday at the University of New Haven and other area schools had 2,700 rounds of ammunition in his padlocked bedroom, along with newspaper clippings about the July 2012 shooting at a theater in Aurora, Colo., a prosecutor said Wednesday.

William Dong, 22, was arraigned Wednesday at Superior Court in Milford on a variety of charges, including illegal possession of an assault weapon.

Police described that weapon as a "Bushmaster .223 Assault Rifle with a collapsible stock," and said that it was banned under state law. A loaded 30-round magazine was in the rifle, police told the Hartford Courant.

Police said the rifle was in Dong's car and that Dong was carrying two handguns when officers found him on the university campus.