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Tragedy and chaos struck during evening rush hour north of New York City Tuesday, when a packed commuter train traveling up to 60 mph struck an SUV straddling the tracks, killing the vehicle's driver and five people aboard the train and sending 400 feet of the electrified third rail up through the floor of a crowded car.

Panicked and bleeding passengers clawed and scrambled through the flaming and twisted wreckage, some exiting through the Metro-North train's car windows following the 6:30 p.m. crash in Valhalla, some 20 miles north of the city. At least 15 more people were injured, including seven seriously. The train's locomotive engineer was among those hurt.

"You have seven people who started out today to go about their business and aren't going to be making it home tonight," New York Gov. Andrew Cuomo said at a press conference late Tuesday.

"I am amazed anyone got off that train alive."

— Rob Astorino, Westchester County Executive

Early Wednesday, Cuomo said the death toll had been revised down to six.

The fiery crash occurred moments after the railroad crossing gates came down on top of a black Mercedes-Benz SUV that had stopped just before the tracks. The SUV's driver, -- whom family friends identified to the Associated Press as 49-year-old Ellen Brody, a jewelry store employee and mother-of-three -- got out to inspect the vehicle, then got back in to move the vehicle. But a witness said she lurched forward, onto the tracks, as the train, carrying as many as 700 passengers, bore down.

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    "It looks like where she stopped she did not want to go on the tracks, but the proximity of the gate to her car, you know, it was dark -- maybe she didn't know she was in front of the gate," Rick Hope, who said he was directly behind the woman and backed up to give her room to do the same, told WNYW.

    When the woman, who was apparently the Jeep's sole occupant, moved forward, the train broadsided the vehicle, pushing it an estimated 10 car lengths down the track before bursting into flames and creating a horrific scene of tangled steel, burning debris and the anguished cries of injured riders. Westchester County Executive Rob Astorino described the train as "completely charred and burned."

    "I am amazed anyone got off that train alive," Astorino added. "It must have been pure panic, with the flames, the third rail and the smoke."

    Passengers were evacuated through the rear train car, with as many as 400 sent to The Cliffs at Valhalla, a rock-climbing gym near the scene for immediate assessment and treatment, said Sgt. Michael McGuinn of the Mount Pleasant, N.Y., police department.

    An art museum curator and investment banker were among the dead, according to The New York Post.

    Walter Liedtke was the curator for European paintings at the Metropolitan Museum of Art, according to Met director Thomas P. Campbell, while Eric Vandercar worked in the city for an investment banking firm and is survived by his wife and two children, according to friends on social media.

    A friend of Vandercar, Peter Glover, wrote on Facebook: “My heart is breaking for Jill and the kids. RIP Eric Vandercar. To know you was to love you, and you will be missed by everyone who was ever lucky enough to meet you … so many people grieving today.”

    The train left Grand Central Terminal in Manhattan at 5:44 p.m. and was due in Southeast at 7:08 p.m. Metro-North Railroad is the nation's second-largest commuter railroad, with main lines running out of Grand Central to northern suburbs in New York and Connecticut. The Metro-North carries on average about 286,000 passengers each weekday over its 795 miles of track, according to MTA.

    It was unclear how fast the train was going, but the maximum would be 60 mph, a railroad official said.

    Passengers on the train said they felt a jolt, then heard a huge explosion.

    "I was horrified — the crash and the flames," passenger Devon Champagne told the New York Post. "I thought I was going to die for a minute. It was the scariest moment of my life."

    The paper reported that some tried to reach passengers in the first car of the train, which sustained the heaviest damage.

    "They were basically trapped in there with the fire," said passenger Jamie Wallace. "A few of us in my car tried to break the glass so we could get through, but to no avail."

    All railroad grade crossings have gate arms that are designed to lift automatically if they strike a vehicle on the way down, railroad safety consultant Grady Cothen said. The arms are made of wood and are designed to be easily broken if a car trapped between them moves forward or backward, he said.

    Early Wednesday, National Transportation Safety Board member Robert Sumwalt said an extensive probe is under way. He said investigators will be on the scene for up to a week, and the probe could last as long as a year.

    “Our goal is not only to find out what happened, but find out why it happened so we can issue safety regulations to prevent it from happening again,” Sumwalt said. He said the train will likely be moved sometime Wednesday and inspectors will work to remove perishable evidence from the scene.

    Metro-North has had high-profile accidents in recent years. Late last year, the National Transportation Safety Board issued rulings on five accidents that occurred in New York and Connecticut in 2013 and 2014, repeatedly finding fault with the railroad while also noting that conditions have improved.

    Among the accidents was a Dec. 1, 2013, derailment that killed four people, the railroad's first passenger fatalities, in the Bronx. The NTSB said the engineer had fallen asleep at the controls because he had a severe, undiagnosed case of sleep apnea.

    The Associated Press contributed to this report.

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