Around 3:45 this morning as I was on my way back from the fire in Lynn I took Route 107 also known as Broadway once you roll into Revere. I was behind Ladder 2 as they were also heading back to quarters from the cover assignment from the earlier fire. We encountered an accident-A Cataldo ambulance which was involved versus a passenger vehicle then into an occupied building at the intersection of Broadway and Mountain Ave. The captain of the truck requested fire alarm to strike the box; Which in turn, bringing additional manpower to the scene. The ambulance was not transporting any patient at the time. There were 2 occupants in the passenger car which collided with the rig and I believe they were transported to an area hospital for an evaluation as precaution. There was significant damage to the foundation of the structure and the building inspector was requested to respond to the scene. Action emergency services arrived to assess the damage and were going to make a new set of temporary stairs that were displaced during the crash. The building was not evacuated.