Christ Olsen Rochelyn, 28, was behind the wheel when the 2004 BMW 325 pinned his uncle, Kesnel Rochelyn, shortly after 6:30 p.m., they said.
The uncle was pronounced dead at the scene, Passaic County Prosecutor Camelia M. Valdes and Paterson Police Chief Troy Oswald said in a joint release.
Both "were working on the vehicle together" when the accident occurred, they said.
City firefighters removed the body from beneath the car nearly 45 minutes later.
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