UPDATE: Around 3:35 p.m., Boston Police broke up what appeared to be a brewing altercation related to the earlier incident at Comm. Ave. and Warren - where they also stopped a Green Line trolley in search of somebody on the train. Police arrested several teens.
School Police today detained a student at the Boston Green Academy, 20 Warren St., after they found him with a gun around 2:20 p.m. The school was put in safe mode until Boston Police arrived to take custody of both him and the gun.
Police requested two ambulances, one for somebody with a dislocated knee, one for an officer who was bitten.