LYNN – The motorcycle involved in a collision Wednesday near 50 South Common St. was stolen, police said Thursday.The operator of the motorcycle remains in critical but stable condition at Mass. General, where, according to Lynn Police, he remains intubated and unconscious.According to a report filed at the Marblehead Police Station, a resident of the town reported, at 9:15 p.m. Wednesday, that his motorcycle had been stolen from his driveway. Shortly thereafter, Lynn Police confirmed that it was the motorcycle involved in the accident, according to the Marblehead log.The accident, which occurred around 5:30 p.m., involved the motorcycle and a car driven by a woman. The motorcyclist struck the woman’s driver-side door, and the car veered into the commons area, landing between trees. Extensive damage was done to both vehicles.The motorcyclist appeared to be traveling at a high rate of speed, according to Lynn Police Sgt. Robert Godbout. The accident is still under investigation, police said.The motorcyclist was thrown from his bike, Godbout said, and his helmet came off and landed across the street.Godbout believes both drivers are residents of Lynn.The driver of the car was reported in stable condition Wednesday night at Salem Hospital, police said.