Weston firefighters responded to the single-vehicle crash on the ramp from Route 30 just before 5 a.m. and saw the car had rolled down the embankment and came to a rest on its roof, officials said in a Facebook post. Crews climbed down and cut the driver from the vehicle in under 10 minutes before carrying them to a waiting ambulance.
Paramedics rushed the driver to an area hospital with critical injuries. Officials did not release the driver's name.
Police shut down the ramp for several hours as they cleared the scene.
Massachusetts State Police are investigating the cause of the crash.
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