Tuesday night’s accident closed the busiest rail corridor in the US, between New York and Washington DC, as investigators began their inquiries into the incident, in which more than 140 people were hospitalised, some with critical injuries.
Amtrak said the train was carrying 238 passengers and five crew members. Last night it was not clear if everyone on board had been accounted for.
President Barack Obama called the section of rail line “a way of life for many” and said he was “shocked and deeply saddened” to hear of the incident.
The New York National Guard will travel to Philadelphia to assist in the response efforts, governor Andrew Cuomo said.
Philadelphia mayor Michael Nutter said: “It is an absolute disastrous mess. I’ve never seen anything like this in my life.”
He said all seven carriages of the train, including the engine, were in “various stages of disarray”, with some “completely overturned, on their side, ripped apart”. The engine was completely separated from the rest of the train, and one of the carriages was perpendicular to the rest of the cars, he said.
The train, travelling from Washington DC to New York, was going into a turn in the Port Richmond area, shortly after leaving Philadelphia’s main station, when it started to shake before coming to a sudden stop.
Paul Cheung, who was on the train at the time, said it “started to decelerate, like someone had slammed the brake”.
“Then suddenly you could see everything starting to shake,” he said. “You could see people’s stuff flying over me.”
Daniel Wetrin was among more than a dozen people taken from the train to a nearby school to be assessed.
He said: “I walked off as if, like, I was in a movie. There were people standing around, people with bloody faces… power cables all buckled down as you stepped off the train.”
Gaby Rudy, 18, a student at George Washington University, had been sleeping in the last carriage when she felt it veer off the tracks and then flip over.
She said the carriage immediately began to fill with smoke, and she called 911. Ms Rudy then saw another young woman on the floor with a back injury, who she helped out of the train.
Former US Republican congressman Patrick Murphy was on the train and tweeted photos of firefighters helping other people in the wreckage. “Pray for those injured,” he said.
Amtrak said rail services on the Northeast Corridor between New York and Philadelphia had been stopped.
The National Transportation Safety Board has dispatched a team, and said the train recorder has been found. Information from this, including train speed, video of the accident, and the engineer’s steering attempts, will be examined.
The area where the derailment occurred is not far from the scene of one of the deadliest train accidents in US history – the 1943 derailment of The Congressional Limited, travelling from Washington to New York, in which 79 people died.