Officials say 16 people were treated at hospitals after two trolleys collided in Boston. Massachusetts Bay Transportation Authority spokesman Joe Pesaturo says the accident occurred around 3:15 p.m. Friday on the Mattapan Trolley line. Boston Emergency Medical Services says it evaluated 17 people at the scene and transported 16 to hospitals. It updated those seen from 13 people evaluated and 12 transported. None of the injuries was believed to be serious. Pesaturo says the MBTA is investigating the accident but has ruled out any connection to the bitter cold weather. He says the investigation will include inspections of the equipment and interviews with the trolley operators. The frigid temperatures were blamed for breakdowns and delays earlier Friday on some of the T's trolley and commuter rail lines.