Officials survey the site of a derailed Amtrak train in Philadelphia, Pennsylvania on May 13, 2015. An Amtrak passenger train with more than 200 passengers on board derailed in north Philadelphia on Tuesday night, killing at least six people and injuring scores of others, several of them critically. 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.
Mike Segar/Reuters
Emergency workers look through the remains of a derailed Amtrak train in Philadelphia, Pennsylvania May 13, 2015. Rescue workers on Wednesday sifted through twisted metal and debris from the wreck of the Amtrak train that derailed in Philadelphia, killing six people and injuring scores of others, as investigators began reviewing data to determine the cause of an accident.
Lucas Jackson / Reuters
Rescue workers searched through the debris on Wednesday for more victims of an Amtrak passenger train wreck in Philadelphia that killed six people and injured scores others. The accident left rail cars mangled, ripped open and strewn upside down in the city's Port Richmond neighborhood along the Delaware River.
Mike Segar/Reuters
Security officials survey the site of a derailed Amtrak train in Philadelphia, Pennsylvania May 13, 2015. Authorities said they did not know what caused the New York City-bound train carrying 243 people to derail on Tuesday night.
Mike Segar/Reuters
Philadelphia Mayor Michael Nutter looks down while giving a news conference near the site of a derailed Amtrak train in Philadelphia, Pennsylvania May 13, 2015. Nutter said authorities had not yet accounted for everyone aboard the train.
Mike Segar/Reuters
U.S. National Transportation Safety Board officials stand on the sidelines of a news conference near the site of the derailed Amtrak train. The U.S. National Transportation Safety Board has opened a broad investigation into the cause of the train derailment north of Philadelphia that left at least six people dead, an official for the agency said on Wednesday.
Mike Segar/Reuters
Robert Sumwalt, an official from the U.S. National Transportation Safety Board, speaks during a news conference with Philadelphia Mayor Michael Nutter (unseen) near the site of a derailed Amtrak train in Philadelphia, Pennsylvania May 13, 2015.
Mike Segar/Reuters
A police officer cordons off the site of the derailed Amtrak train.
Mike Segar/Reuters
Rescuers work around derailed carriages of the derailed Amtrak train in Philadelphia, Pennsylvania, on May 13, 2015.
Jewel Samad/AFP/Getty
Passengers injured in an Amtrak train derailment, who were bused from to New York from Philadelphia, get assistance from the Red Cross at Penn Station May 13, 2015 in New York.
Timothy A. Clary/AFP/Getty
Rescue workers search for victims in the wreckage of a derailed Amtrak train in Philadelphia, Pennsylvania May 12, 2015.
Bryan Woolston/Reuters
