The Amtrak train that derailed in Philadelphia, killing at least seven people, was traveling 106 mph as it moved through a curve where the speed limit was 50, the National Transportation Safety Board announced on Wednesday.
The unnamed engineer slammed on the emergency braking system and the speed fell to 102 mph three seconds later, NTSB board member Robert L. Sumwalt said at an afternoon news conference. The train then derailed, sending the locomotive and seven passenger cars off the tracks, Sumwalt said.
His comments offered the first detailed look at Tuesday's tragedy involving the Amtrak Northeast Regional Train 188 that departed Washington bound for New York. The train, carrying 238 passengers and a crew of five, had just left the 30th Street station in Philadelphia when it derailed at 9:21 p.m.
It was going through a left-hand curve when the train careened off the tracks, Sumwalt said.
The findings were preliminary, but investigators said they were confident the speed estimates were accurate to within 1 or 2 mph, Sumwalt said. Investigators have not yet determined when the train began moving faster than the speed limit. Right before the curve the speed limit is 80 mph, he said.
"We are here to collect perishable evidence that will go away with the passage of time," he told reporters. Analysis will come later.
The NTSB plans to talk to the engineer, crew members and passengers and analyze brakes and train control signals.
"Our mission is to find out not only what happened by why it happened so we can prevent it from happening again," Sumwalt said.
More than 200 people were injured, eight of them in critical condition.
"Almost everyone had rib fractures," said Dr. Herbert Cushing, chief medical officer at Temple University Hospital. "And I think we're fortunate there were not more deaths."
Not all of the passengers and crew members have been accounted for, Philadelphia Mayor Michael Nutter said earlier. Rescuers were still searching through the mangled wreckage Wednesday afternoon.
"The search is very, very active," Nutter told reporters. "We will not cease our efforts until we are absolutely sure."
Amtrak 188 traveled through the heavily used Northeast Corridor and pulled into the working-class area known as Frankford Junction. The accident site is not far from where one of the nation's deadliest train accidents occurred — the 1943 derailment of the Congressional Limited, from Washington to New York, which killed 79 people.
The stretch of tracks where the derailment occurred is not equipped with a safety system called Advanced Civil Speed Enforcement or positive train control, Sumwalt said. Such sytems use GPS, digital radio communications and computers to monitor trains and automatically override the engineer and apply brakes to prevent an accident.
Amtrak has such a system on most of the Northeast Corridor, Sumwalt said.
"Based on what we know right now, we feel that had such a system been installed in this section of track, this accident would not have occurred," Sumwalt said.
On Wednesday, passengers described a jolt and the chaos inside the train as the cars pulled to the side, tossing people like dice.
The internal turmoil and heroism were captured on cellphone cameras and video that quickly went viral. The train also carried the usual complement of politicians and journalists heading home from a day at the nation's capital.
Passenger Janelle Richards, a producer for "NBC Nightly News," posted a video on Twitter she took on a train car, moments after the crash, showing passengers attempting to push open a door and exit the train.
"Go, go, go, go," a man says.
"Can you help me?" a woman pleads.
Among those on the train was Patrick Murphy, a former Democratic congressman from Pennsylvania.
"I feel like I'm a lucky son of a bitch," he said in a telephone interview. He said he was in the cafe car, listening to music on his headphones and working on his iPad after eating a pulled pork sandwich, when the train began vibrating violently.
Murphy, who was seated at a bench, noted that there were no armchairs for the 11 people in his car. The server who had been standing behind the counter was "pushed back and forth like a pinball."
Murphy, a 200-pound Iraq war veteran and MSNBC host, said he was thrown into the air as well.
"I just checked my arms and legs," he said. "They were there. They were working."
Officials from the city, the NTSB and Amtrak said they had recovered the train's "black box" data recorder and expressed their condolences to the families of those who died.
"We express our deepest sorrow," said Nutter, echoing statements from top government and transportation officials. "We are heartbroken. We have not experienced anything like this in modern times."
One of the dead, Justin Zemser, 20, was a midshipman from the U.S. Naval Academy who was traveling home on leave, officials said. An Associated Press video software architect was also among the dead. He was identified by the news service as Jim Gaines, a 48-year-old father of two, who was returning to his home in Plainsboro, N.J.
A third victim was identified by Wells Fargo as Abid Gilani, a senior executive in the bank's Commercial Real Estate division.
"This is a tragedy that touches us all," President Obama said in a statement, which called Amtrak "a way of life for many" who live along the Northeast Corridor.
The president praised first responders and the passengers who helped one another during the frantic early moments.
"Philadelphia is known as the city of brotherly love -- a city of neighborhoods and neighbors -- and that spirit of loving kindness was reaffirmed last night," Obama said.
Vice President Joe Biden, one of the most prominent users of Amtrak, offered his prayers as well.
"The victims could have been any one of our parents, children or someone from one of our communities," the vice president said. "Amtrak is like a second family to me, as it is for so many other passengers. For my entire career, I've made the trip from Wilmington [Delaware] to Washington and back. I've come to know the conductors, engineers and other regulars — men and women riding home to kiss their kids goodnight — as we passed the flickering lights of each neighborhood along the way."
At the scene, all seven cars of the Amtrak train were askew in the wreckage. One car appeared to be collapsed like an accordion, three cars were overturned, and three others were a twisted mess.
Hundreds of workers used earthmovers and cranes at the scene, a working-class area with rail yards, warehouses and homes. The search for survivors remained the top priority as rescuers searched the wreckage.
Along with the NTSB, the Federal Railroad Administration is investigating the crash.