Four people have died and eight others were injured after a van shuttling factory workers home overturned on a New Jersey highway, authorities say.
The victims were riding in a Ford Econoline E350 passenger cargo van when it flipped on the Palisades Interstate Parkway in Englewood Cliffs early Friday morning, according to a press release from Palisades Interstate Parkway Police Department, obtained by PEOPLE.
Officials had to extract "several passengers" from the vehicle after they became trapped, Palisades Interstate Parkway police said in Friday's release.
Four of the 12 people on board at the time were pronounced dead at the scene after suffering "severe trauma," officials said. Although they have not been publicly named, WPIX reported that three men and one woman died.
Eight other victims were transported to area hospitals with injuries "ranging from severe head trauma to minor physical complaints," per Friday's release. Additional information has not been made available.
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The van served as a shuttle "for workers in factories in upstate New York," police said in Friday's release.
Family members of two female victims told NBC New York that the shuttle was bringing workers back to New York City from Chester. Family members told the outlet the factory was for "a major global designer and manufacturer of party goods."
Police also said the passengers were returning home from work and would be dropped off in the Tri-State area, according to WPIX.
It is unclear what caused the crash, police said in Friday's release. An investigation into the incident is underway.
The southbound lanes of the highway were briefly closed for motorists, beginning at Exit 2, as officials investigated the crash early Friday morning, according to WPIX.
Police said the lanes have since reopened.