Three men are facing arson charges in connection with a fire at a former McDonald’s restaurant in West Roxbury on Friday night. The fire caused about $100,000 in damage to the vacant building at 1663 VFW Parkway, the Fire Department wrote on its official Twitter feed. No one was injured. Police said in a statement on Saturday that the suspects were arrested after investigators followed footprints leading from the back door of the restaurant to the Charles River. One of the suspects allegedly told police that the fire began accidentally. Police identified the suspects as Denis Florez, 18, of Roslindale; Mark Collins, 18, of West Roxbury; and James McManus, 19, of West Roxbury. They are each charged with arson and breaking and entering. Florez and Collins were arrested, and McManus has been summonsed to court, police said.