At least six people have been killed after a train derailed near Philadelphia, leaving 10 carriages overturned.

Some passengers climbed out of windows to get away from the Amtrak train, which was reported to have been travelling at around 60mph when it left the tracks.

More than 140 people have been taken to hospital, six of them with critical injuries.

Philadelphia mayor Michael Nutter described the scene as "an absolute disastrous mess" and said not all of the more than 240 people on board have been accounted for.

He said: "I've never seen anything like this in my life. It is a devastating scene down there.

"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."

The train, which was travelling from Washington DC to New York, was carrying 238 passengers and five crew members.

It 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. The front of the train is really mangled. It's a complete wreck. The whole thing is like a pile of metal," he said.

Daniel Wetrin, who walked off the train, said it was like something out of a film.

He said: "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."

Roads around the crash site have been blocked off, and people have been told not to go to the scene.

Several of those injured, including one man complaining of neck pain, were taken away on stretchers.

The cause of the crash is being investigated.

Amtrak workers are examining the wreckage and a team from the federal National Transportation Safety Board will arrive at the site later on Wednesday.

Patrick Murphy was on the train:

Originally published at 7.21am