The minivan had slammed into a utility pole, splitting it at the base, on East Saddle River Road south of Lake Street just after midnight Thursday, Capt. Edward Kane said.
The engine block was already starting to cook when Officer Tim Erstling arrived, Kane said.
Erstling immediately pulled the 29-year-old Pomona, NY driver out and away from the minivan, the captain said.
"Minutes later, the vehicle was fully engulfed," he said.
Sgt. Michael Spina helped render first aid before members of the Upper Saddle River Volunteer Ambulance Corps and paramedics from The Valley Hospital in Ridgewood took over, Kane said.
The driver was taken to Hackensack University Medical Center with serious injuries, he said. His condition couldn't immediately be determined.
Members of the Upper Saddle River Volunteer Fire Department extinguished the fire. Orange and Rockland responded to make repairs. PSE&G responded, as well.
Kane thanked Montvale and Saddle River police for their assistance.
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