Five people have been killed after a train derailed and tipped over in Philadelphia.
Six have been critically injured and 130 have been taken to hospital injured in the crash in which 10 carriages of the Washington-New York Amtrak service went off the track on Tuesday evening.
More than 240 were on the train and emergency officials and fire-fighters are at the scene looking for passengers who may be trapped in the wreckage.
It is not known what caused the derailment.
The National Transportation Safety Board said it was dispatching a team of investigators to the crash site.
Mayor Michael Nutter described the scene as horrific.
He said: “It is an absolute, disastrous mess. I’ve never seen anything like this in my life.
“We walked the entire length of the train area, and the engine completely separated from the rest of the train, and one of the cars is perpendicular to the rest of the cars. It’s unbelievable.”
Train 188, a Northeast Regional service, had left Washington DC for New York City.
The front of the train was going into a turn when it started to shake before coming to a sudden stop.
Passenger Paul Cheung said: “The train started to decelerate, like someone had slammed the brake.
“Then suddenly you could see everything starting to shake. You could see people’s stuff flying over me.”
Mr Cheung said another passenger urged him to escape from the back of his carriage, which he did.
He said he saw passengers trying to escape through the windows of carraiges tipped on their sides.
Another passenger, Daniel Wetrin, was among more than a dozen people taken to a nearby primary school afterwards.
“I think the fact that I walked off (the train) kind of made it even more surreal because a lot of people didn’t walk off,” he said.
“I walked off as if, like, I was in a movie. There were people standing around, people with bloody faces. There were people, chairs, tables mangled about in the compartment … power cables all buckled down as you stepped off the train,” he added.
The area where the derailment occurred is known as Frankford Junction and has a big curve.
It is not far from where one of the deadliest US train accidents occurred: the 1943 derailment of the Congressional Limited, from Washington to New York, which killed 79 people.