A locked switch is being blamed for the collision between an Amtrak passenger train and a freight train that killed two people and injured more than 100 others in South Carolina early on Sunday.
The head of the National Transportation Safety Board said a switch on the tracks, which the freight hauler CSX owns and operates, was padlocked in a position that steered the Amtrak train onto a siding near Columbia, S.C., where it crashed into a parked, unoccupied CXS train.
"Key to this investigation is learning why the switch was lined that way," Robert Sumwalt, the chairman of the NTSB, told reporters at a news conference on Sunday. NTSB officials were not immediately available to elaborate.
Amtrak President and Chief Executive Richard Anderson told reporters Sunday that CSX was responsible for the wreck because of the locked switch. CSX officials were not available for comment.
Officials from both companies expressed condolences to the families of the two people killed, an Amtrak engineer and a conductor.
Two of the 116 people injured remained in critical condition overnight, officials said. Specifics were not available.
A team from the NTSB is expected to be on the scene for five to seven days. No probable cause will be issued at that time, the agency told media outlets.
Robert Sumwalt, chairman of the U.S. National Transportation Board, told a news conference the section of track was operated by CSX and there was a padlock on the switch that steered train traffic onto the siding.
"Key to this investigation is learning why the switch was lined that way," he said, calling the damage to the locomotives "catastrophic." An NTSB investigation team was at the site.
Amtrak engineer Michael Kempf, 54, of Savannah, Georgia, and conductor Michael Cella, 36, of Orange Park, Florida, were killed, Lexington County Coroner Margaret Fisher told reporters. Autopsies were being conducted, she said.
Two of the 116 people injured were in critical condition after the wreck, which occurred about 5 miles (8 km) southwest of the state capital, Columbia.
"It's a horrible thing to see, to understand what force was involved," South Carolina Governor Henry McMaster told reporters. "The first engine of the freight train was torn up, and the single engine of the passenger train is barely recognizable."