Amtrak Train 91 was carrying 139 passengers and eight crew members to Miami from New York when it hit the freight train at about 2:35 a.m. local time (0735 GMT) near Columbia, South Carolina's state capital, and derailed, the railroad said in a statement.
Killed were Amtrak's engineer Michael Kempf, 54, of Savannah, Georgia, and conductor Michael Cella, 36, of Orange Park, Florida, Lexington County Coroner Margaret Fisher said on Sunday. Autopsies are under way, she said at a news conference.
"It appears Amtrak was on the wrong track," South Carolina Governor Henry McMaster told a news conference. He said the freight train, which had no one aboard, "was on the track it was supposed to be on."
The area has three rows of tracks, and the freight train was parked on a "loading track or a side track" and "not the main track," McMaster said.
"It's a horrible thing to see, to understand what force was involved," he said. "The first engine of the freight train was torn up, and the single engine of the passenger train is barely recognizable."
The southbound passenger train's locomotive was lying on its side, and the first car was bent and also derailed, although it remained upright, according to images from the scene in the small city of Cayce, South Carolina.
At least four cars of the freight train, which was northbound before it was parked, were crumpled, looking like crushed tin foil, but remained on the tracks.
The passenger train was part of Amtrak' Silver Star Service, and the wreck occurred about 5 miles (8 km) southwest of Columbia. Officials said some 5,000 gallons of fuel leaked as a result of the collision, but it was under control and no threat to public safety.
The number of injured rose to 116 from a previous count of 70, said Lexington County spokesman Harrison Cahill.
"The injuries range from cuts and bruises to severe broken bones," said Derrec Becker, public information officer for the South Carolina Emergency Management Division. "All the injured have been transported to local hospitals."
McMaster said he had been told the Amtrak train's speed was about 59 miles (95 km) per hour upon impact, although the National Transportation Safety Board would investigate the crash.
One priority is recovering data recorders from the Amtrak train that will indicate its speed upon impact, NTSB Chairman Robert Sumwalt told Fox News.
The Lexington County Sheriff's Department said a shelter for passengers was set up at a nearby middle school. Everyone was off the train, and the Red Cross was assisting them, the department said on its website.
Derek Pettaway, a passenger in one of Train 91's rear carriages, told CNN he was sleeping as he headed for Orlando but was awakened by the impact. He said the crew came through the cars "really quickly" and got everybody off the train.
"Nobody was panicking," said Pettaway, who was discharged from a hospital with minor whiplash. "I think people were more in shock than anything else."
In December, three people were killed when an Amtrak passenger train derailed in Washington state. The engineer later told the NTSB he had misread a signal and tried to brake before the accident.
In late January, an Amtrak train carrying Republican members of the US Congress killed one person in a garbage truck with which it collided in Virginia.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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