Passenger David Chavez, 27, of Livingston "exited" a Kenworth tractor pulling a flatbed trailer as it headed south on the highway in Riverdale shortly before 6 p.m. Saturday, April 9, New Jersey State Police Sgt. Philip Curry said.
Chavez's father, who was driving, told responders that his son "just opened the door out of nowhere" and pitched onto the highway's southbound side in Riverdale, one said.
"Luckily he wasn't struck by anyone," a responder said.
Several passing drivers stopped and rushed to help the victim. A medical chopper was requested and then canceled.
Responders used a defibrillator to get a pulse before Chavez was taken by ambulance to St. Joseph's University Medical Center in Paterson, responders said.
Curry characterized his injuries as serious.
Route 287 remained closed temporarily at Route 23 as State Police investigated.
"There is no further information available," Curry said shortly before 7:30 p.m. Sunday.
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