TARRYTOWN, N.Y. (CBSNewYork) — A chain-reaction crash shut down the Gov. Mario M. Cuomo Bridge in both directions Wednesday morning, leaving drivers stranded for hours.

Two northbound lanes and two southbound lanes on the bridge are now open, but drivers are being urged to seek alternate routes and should expect delays.

Witnesses say it all started around 9:30 a.m. when a tractor-trailer driving toward Rockland County jackknifed, setting off a series of crashes involving 25 vehicles, CBS2’s Elise Finch reported.

Four people were injured – the most serious a woman who was trapped inside her car.

“She was hit broadside by a tractor-trailer, hit a couple more cars and then became pinned in the vehicle,” Warren Kremin, of New City, said. “When I got there she was kind of unconscious and appeared to be in shock actually. So just kind of kept her from moving and kept her stabilized until emergency services can get there.” 

Snow and sleet were largely to blame, Finch reported.

“The roadway surface was extremely slick and it became slick very quickly. I would say the snow probably was dropping at a rate of at least an inch an hour,” New York State Police Captain George Mohl said. “It started coming down pretty heavy.”

Hundreds of drivers were stuck in traffic for hours – on the bridge and the roads leading to it.

“My brother called me and he said, ‘oh the bridge is closed,'” said driver Wilder Umana. “I never believe anything he says, so now I’m stuck here.”

“Sitting for a half an hour is one thing, but sitting for a couple of hours, it’s definitely gonna screw up the day,” another driver said.

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