The 34-year-old woman and her husband had taken their three children with them to an overnight cleaning assignment at Ramsey Infiniti, responders told Daily Voice.
The father apparently pulled the family's Honda Accord out of the Infiniti lot into the right lane of southbound Route 17 -- a treacherous stretch of road -- as a Dodge Durango was clearing the crest of the hill around 6:45 a.m., they said.
One of the couple's pre-teens was in the passenger seat next to his father, they said.
The other was in the back seat with her mother, who was sitting behind the father.
The infant was in the car seat on her mother's lap, responders said.
The Durango slammed into the back of the Accord, sending it into a vehicle parked at the Joe Heidt Motors Corp. Volkswagen dealership.
The woman and her baby were ejected -- the infant still strapped in the car seat -- as the Accord spun, kept going and hit the divider, responders said.
The mother was thrown into a vehicle in the lot and landed below the front bumper, they said. She died moments after being carried onto a strip of grass along the highway.
The baby landed face-down on the highway in the car seat.
A first responder from Mahwah who was passing by stopped. So did two off-duty police officers -- one from Ramsey, the other with the NYPD.
The four surviving family members were brought to Hackensack University Medical Center with minor injuries, including road rash on the baby's face.
The Bergen County Prosecutor’s Fatal Accident Investigations Unit was investigating. The Bergen County Sheriff’s Bureau of Criminal Identification collected evidence.
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