Denver SWAT responded when a cleaning crew working late at night notified authorities of two suspects with guns and backpacks entering KIPP Montbello College Prep Middle School, reports The Denver Post. Two male juveniles were arrested. It was later determined that the weapons were BB guns.
Police brought a bomb squad on scene in addition to SWAT, as the suspects' intent was unclear. Officers saw the two individuals on security cameras and attempted to communicate with them over the school's public address system for hours before apprehending them.
After a campus sweep, authorities found the "assault rifles style" BB guns and backpacks full of various items the suspects were believed to be stealing, according to a tweet from Denver Police.