Amtrak Train was Belting Along the Tracks at Twice the Speed Limit When It Derailed

The Amtrak train that flew off the tracks in Philadelphia killing seven people and injuring more than 200 others was speeding along the rail at twice the speed limit it was supposed to, authorities said today.

Amtrak Northeast Regional Train 188 derailed around 9:30pm Tuesday night along a sharp turn as it traveled from Washington DC to New York City. The National Transportation Safety Board (NTSB) confirmed that preliminary data indicates the train was traveling 100 mph at the time of the crash. The legal speed along that curve is 50 mph, according to the Federal Railroad Administration.

The update from the NTSB came Wednesday afternoon, but the organization did not indicate what may have caused the crash. Passengers described feeling the train suddenly decelerate, start to shake, and flip over, ripping the front carriages apart. Some were catapulted from their seats into the luggage racks as up to 10 cars of the train veered off the track.

Many passengers were able to walk away but others were left trapped in the mangled wreckage. At least 130 were taken to hospital originally, six in a critical condition, according to the Associated Press. According to an update Wednesday afternoon from Temple University Hospital, where the victims were taken, 23 patients remain, most of whom are in stable or better condition. More than 200 people were injured in total.

"Things start flying… phones, laptops — then people," passenger Jeremy Wladis told CNN. "Seats, trays start flying, you hear bumping, like metal mangling, but it happened so quickly, you didn't even know what was going on. Then we got out, and we saw the train, and it looked like a pretzel. Turned, and twisted, wires ripped out, electrical live wires, it was just chaos."

Amtrak train derailed. Loud crash. Smoke filled the train. People that were able to walk to an exit tried to get door open and climb off.

— Janelle Richards (@Janelle_News) May 13, 2015

Video I took moments after crash. People trying to open the door and get off the train. pic.twitter.com/fJ2bxXfmhG — Janelle Richards (@Janelle_News) May 13, 2015

"I was actually sleeping on the train and all of a sudden… I felt it veer off the tracks," George Washington University freshman Gaby Rudy told New York Daily News. "I was just tumbling and I got thrown to the other side of the train. And the train flipped over almost completely. And I guess the windows smashed because we climbed out a window."

Joan Elfman, a nurse who was one of the 243 people onboard, told CNN-affiliate KYW when she saw the destruction around her she thought she was in a nightmare. "It can't be happening," she described thinking. "I saw so many head injuries and bloody faces. There were a lot of fractures — arms, shoulders, all kinds of fractures," she said.

Philadelphia Mayor Michael Nutter visited the crash site, telling reporters it was "an absolute disastrous mess. I've never seen anything like this in my life."

It is not known what caused the derailment, which happened on a four-track section in the Port Richmond section of Philadelphia near the Delaware Expressway, shortly after the train had left the city's main station.

The route is part of Amtrak's Northeast Corridor, the busiest railroad in North America which comprises 363 miles of track which links Washington to Boston. Each day it carries more than three times more people between the US capital and New York City than planes do, said CNN.

Follow Miriam Wells on Twitter: @missmbc