Firefighters rescued a man who was trapped under a tractor trailer following a five-vehicle crash on Interstate 495 early Monday, State Police said. The tractor trailer was traveling south near Exit 41 when it crashed into the back of a van just after 6 a.m., State Police said. The passenger in the van was ejected from the vehicle and the tractor trailer ran over him and came to a stop on top of his legs. Firefighters used muscle power and large inflatable bags to lift the trailer off the victim, officials said. He was taken to Lawrence General Hospital with serious injuries.