A New York City-bound Amtrak train derailed in Philadelphia on Tuesday, overturning and mangling the cars and flinging passengers and luggage around inside. At least six people were killed and at least 140 injured.
The victims included at least eight who were critically hurt in the accident, which closed the nation's busiest rail corridor.
The death toll climbed on Wednesday morning when Temple University Hospital confirmed a sixth fatality. A rescue worker at the scene had told NBC News that authorities feared the death toll could rise as they had been unable to get underneath the toppled cars.
The Amtrak Regional 188 was traveling to New York from Washington, D.C., and carrying 238 passengers and 5 crew members when the train derailed at around 9:30 p.m. ET.
"It is an absolute disastrous mess," Philadelphia Mayor Michael Nutter told reporters after visiting the scene of the crash. "Never seen anything like this in my life." He said there were cars "completely overturned, on their side, ripped apart."
A spokeswoman for the National Transportation Safety Board and a spokesman for the FBI said there were no early indications that it was anything other than an accident.
The front of the train was going into a turn when it shook, witnesses said. Two sources told NBC News the train went off the track at a point where a 70 mph stretch goes into a 50 mph curve, but they cautioned it is too early to know whether the curve or speed were factors.
"We were rolling along nice and smooth and then all of a sudden we were on our side," passenger Don Kelleher told NBC Philadelphia.
All six train cars and the engine derailed in the crash and some cars fell on their sides, flinging passengers and luggage around, survivors and officials said.