We've learned more information about a terrifying accident in the Lower Hudson Valley. A tractor-trailer fell off an overpass and crushed a car below.

Last Wednesday, New York State Police began investigating a fatal crash involving a tractor-trailer that occurred on I-287 (Cross Westchester Expressway) in the town of Harrison, Westchester County.

New York State Police investigate fatal crash on I-287 in Westchester County

CBS New York/YouTube
CBS New York/YouTube

On Jan. 18, around 10:20 a.m., a tractor-trailer was on the Exit 9A ramp from I-287 to I-684 north when the driver lost control and flipped over the guard rail and onto the I-287 westbound lanes, police say.

The driver of the tractor-trailer was pronounced dead on the scene. An occupant from an involved vehicle on I-287 was taken to the hospital.

All westbound lanes of I-287 are closed at Exit 9, and the left lane is closed eastbound. Traffic diversions are in place.

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Update: 1 Dead, 1 Injured In Lower Hudson Valley Crash

CBS New York/YouTube
CBS New York/YouTube

In an update, New York State Police identified the people involved in the crash.

State Police identified the deceased tractor-trailer driver as Nathan L. Montalvo, 42 of Guilford, CT.

The injured motorist is identified as 37-year-old Aris Guerrero of West Hempstead, New York.

Guerrero was transported to Westchester Medical Center for treatment of his injuries. His condition was not released.

New York State Police Seek Help

CBS New York/YouTube
CBS New York/YouTube

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The crash remains under investigation, and the State Police Bureau of Criminal Investigation is asking anyone who may have witnessed the crash to please contact Investigator Hettinger at (914) 769-2600.

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Video from the scene can be seen below:

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