Police reveal cause of Palisades Parkway crash that killed 4

The driver of a passenger van carrying warehouse workers may have had a medical emergency before the vehicle overturned on a major highway in northern New Jersey, killing four people and injuring eight others, authorities said

The crash on the Palisades Interstate Parkway in Englewood Cliffs occurred shortly before 1:30 a.m. Friday. The van ended up in the center median of the southbound lanes of the highway, leaving the driver and all the passengers trapped inside the vehicle.

Lt. Raymond Walter of the Palisades Interstate Parkway Police said statements from van passengers led investigators to believe that the driver, George Massey, 44, of Bronx, N.Y. had an unspecified medical issue before the accident.

Massey died in the crash, along with passengers Jose Luis Romero Munoz, 59, also of the Bronx, and Clara Estrella, 49, and Candida Frias, 59, both of New York. Eight more passengers were taken to nearby hospitals with injuries ranging from severe head trauma to minor physical complaints, police said.

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Walter said the van was heading back to New York City from the Amscan Warehouse in Chester, N.Y.

Party City, the parent company of Amscan, a party supply business, said in a statement that the Chester distribution center had "suffered the loss of three valued team members" and offered "our most heartfelt condolences" to their families and friends, NJ.com reported.

"We pray for the recovery and healing of the additional team members injured in the accident," the statement said.