The legally parked dump truck was rammed from behind by a Lexus ES 350 outside a Hampshire Road home where D.S. Masonry of Woodcliff Lake was doing work, Capt. John Calamari said.
Those who heard the crash and came running found a 37-year-old worker from West New York unconscious on the lawn with his head at the curb line, Calamari said.
It was initially unclear whether he was struck by the sedan or was on the back of the truck when it was hit.
The driver, who wasn't injured, said she couldn't remember what happened, Calamari said. There were no witnesses.
The victim, meanwhile, was taken to Hackensack University Medical Center. Township detectives will interview him once he's able, the captain said.
The woman received a summons for careless driving, he said.
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