Concord Police and Fire responded to the crash in which a vehicle left Lowell Road near Macone Pond and drove into the Assabet River around 2:30 p.m. on Monday, May 1, both departments report.
The car stopped in an area of about three feet of water, according to authorities. An off-duty officer and bystander tried to free the driver, but were unsuccessful.
Concord Fire came shortly after and were able to free the driver by off cutting a door with hydraulic tools, both departments said.
The driver was eventually taken by ambulance to a landing zone at the Fenn School where they were flown to a Boston-area trauma center. Their condition was not specified.
No other vehicles were involved in the crash and the driver was the sole occupant of the car, authorities added. The crash remains under investigation.
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