Both victims are longtime township residents in their late 80s, Police Chief Glenn Hooper said shortly after the crash on Koch Peak.
Their Honda Accord mounted a curb between two streets signs, crossed Washington Avenue and crashed into a stone retaining wall on the other side, he said.
The chief secured the scene and helped administer first aid along with Officers Vincent Montalbano, Heather Castronova and Vincent Santa.
AirMed One flew the woman to Hackensack University Medical Center. Hillsdale Ambulane brought her husband to HUMC.
Township firefighters disconnected the battery and assisted in security the crash scene so the couple could be removed from the car, Hooper said.
Hillsdale firefighters assisted in securing the landing area at Memorial Field, he said.
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