The crash took place around 415 p.m., Wednesday, Jan. 1, on Martin Luther King Drive, in the area of UPS, said Norwalk Fire Department Deputy Chief Edward Prescott.
A Norwalk firefighter who was on his way to work came upon the accident and rushed to help.
He found the driver of a BMW unconscious, and immediately began offering aid, as Norwalk Police arrived on the scene, Prescott said.
He was assisted by the first arriving police officers in getting the driver off the embankment to the sidewalk.
A firefighter drove the ambulance while the paramedics tended to the patient.
A second ambulance transported two other patients, with non-life threatening injuries, Prescott said.
There were no injuries in the third vehicle.
Norwalk Police are investigating the cause of the accident, Prescott added.
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