The NYPD said the westbound side of the upper level of the George Washington Bridge was temporarily closed on Tuesday night due to a deadly shooting.

The Port Authority Police Department, which is heading up the investigation, said it received reports just after 7 p.m. of a single-vehicle crash mid-span. When officers arrived on the scene they found the driver of the vehicle with a gunshot wound to the head. The man was taken to Englewood Medical Center in critical condition, but later died, the NYPD said.

Police said the circumstances surrounding the shooting were not immediately known and no arrests have been made.

Due to the shooting, all lanes on the westbound side of the bridge were closed, creating a major traffic problem for people trying to get out of New York City. Chopper 2’s Dan Rice said one factor complicating things is commercial vehicles can only use the upper level of the bridge.

There was no immediate word on when the westbound lanes would be reopened.

The closure caused a massive backup across the Bronx to the Major Deegan Expressway, Rice reported.

Traffic was crawling on the eastbound side of the bridge heading into the city.

Please stay with CBS News New York for more on this developing story.

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