An Amtrak passenger train with more than 200 passengers on board derailed in north Philadelphia on Tuesday night, killing at least five people and injuring scores of others, several of them critically, authorities said.
Authorities said they had no idea what caused the train wreck at about 9:30 p.m. local time that left some rail cars mangled, ripped open and strewn upside down and on their sides in the city's Port Richmond neighborhood along the Delaware River.
Survivors described scenes of horror and chaos as passengers and luggage were tossed about careening train carriages.
Philadelphia Mayor Michael Nutter told a news conference that at least five people were killed in the accident. He later said 65 others were taken to area hospitals, six of them critically injured.
Philadelphia-area hospitals and health systems collectively reported taking in 135 patients from the wreck.
"It's an absolute disastrous mess," Nutter said. "I've never seen anything like this in my life."
Amtrak said there were 238 passengers and five crew members aboard the derailed No. 188 train on route from Washington, D.C., to New York. Seven cars, including the engine, left the tracks, according to the mayor.
"I cannot say everyone is accounted for at this time," he said, briefing reporters again well past midnight.
The national government-backed passenger rail line provided no other details about the circumstances of the accident. It said Amtrak service along its busy Northeast corridor between New York and Philadelphia had been suspended. Nutter later said he doubted the service could be restored through Philadelphia this week.
CNN quoted the Federal Bureau of Investigation as saying there was no indication that terrorism may have been a factor in the derailment. Three law enforcement officials contacted by Reuters also said they have not encountered anything suspicious. The weather was fair at the time of the crash.
"We do not know what happened here. We do not know why this happened," Nutter told reporters. "There's no information about that." He later told CNN there was no indication that the train derailed due to a collision with another train.
He also said the train derailed on a curved stretch of track, adding: "We have no idea what kind of speed we're talking about."
Television footage broadcast on MSNBC showed dozens of emergency workers scrambling around the wreckage with flashlights, with train cars strewn about in a zig-zag pattern. Photos from the scene showed emergency personnel loading injured people onto stretchers and backboards.
Former Pennsylvania Congressman Patrick Murphy, who was a passenger on the train, told MSNBC that the cafe car he was riding in flipped over, but he escaped with minor cuts and bruises.
He estimated the train was traveling at about 60 or 70 miles per hour (96-113 kph) when "all of a sudden, it went off the rails."
U.S. Senator Tom Carper of Delaware had been on the train but got off at Wilmington, Delaware, before the crash, he said in a Twitter message.
Passenger Daniel Wetrin, riding in the train's last car, told CNN by phone he was thrown onto the floor and into the aisle as his carriage left the tracks.
"Chairs were flying around, people were flying, bags, pretty chaotic," he said. "There were two people above our heads in the luggage rack."
Moments later, people came to their senses and after a couple of minutes they managed to open a rear door and walk off. He said there were no major injuries on his carriage.
Port Richmond is a working-class neighborhood that has recently become a popular place to live among younger adults in the city.
Sharon Achuff, 51, who lives along the tracks about 200 yards (meters) from the wreck, said she was sitting on her front stoop when she saw a bright, flashing blue light, followed by a loud boom.
In a video posted on social media, passengers could be heard crying and others were telling victims to crawl forward.
The National Transportation Safety Board said it had launched a "go-team" to investigate the crash and that they were gathering information.
The crash was the latest in a series of rail accidents on heavily traveled passenger train routes over the past year.
In March, 21 people were injured in Los Angeles when a commuter train struck a car that turned in front of it, a month after 50 people were hurt and an engineer fatally injured when a Los Angeles-bound Metrolink train struck a pickup truck.
In February, six people were killed and a dozen injured when the Metro North commuter train they were riding in north of New York City hit a car stalled on the tracks during rush hour. The driver of the vehicle also died.
