The Amtrak train that jumped the tracks late Tuesday evening near Philadelphia was likely traveling at 106 miles per hour when it approached a bend in the rail where the limit is 50, the National Transportation Safety Board (NTSB) confirmed on Wednesday. The emergency break appears to have been applied just seconds before the derailment, which killed at least seven people and left around 200 injured. And about 24 hours after the deadly crash, Philadelphia Mayor Michael Nutter told msnbc's Rachel Maddow that the search and rescue effort at the scene continues "to be sure as best we can be that we have accounted for everyone who was on that train."
Nutter told msnbc earlier Wednesday that "unless something really went wrong with the engineer," identified as Brandon Bostian by NBC News, it appears that what occurred was a "preventable accident." Nutter added, "We know now what happened but we still don't know why."
Bostian has handed over his cell phone to Philadelphia police and gave a blood sample, according to NBC affiliate WCAU. Bostian spoke at least briefly to police Wednesday and is expected to sit for another interview in the future, according to the report. Police said no one has been named as a suspect in the crash.
The train's high speed is the latest clue in the events leading to the derailment along the busiest rail corridor in the country. Several passengers remained unaccounted for on Wednesday afternoon as authorities worked to find answers from the train's event data recorder, which was recovered in the wreckage.
The Amtrak Regional 188 traveling to New York City from Washington, D.C., had 238 passengers and five crew members on board when it abruptly careened off the tracks just north of Philadelphia Tuesday evening. The train surged forward with such force that all seven train cars and engine derailed from the tracks, overturning some cars and sending some passengers flying.
According to Robert Sumwalt, an NTSB board member, had an Advanced Civil Speed Enforcement System (or ASCES) -- a program which is designed to keep trains below their speed limit -- been installed in the area this derailment probably "would not have occurred."
“To see these cars, huge metal, turned upside down, one basically split in half, most of the cars either upside down, on their side or tilting, the engine completely separated ... you know this is a devastating situation,” Mayor Nutter said during a press briefing on Wednesday. "It is incredible that so many people walked away from the scene that night."
Still by midday, the death toll continued to rise. Among those identified were 20-year-old U.S. Navy midshipman Justin Zemser, the Naval Academy said via Twitter, Abid Gilani, an executive at Wells Fargo, Rachel Jacobs, the CEO of ApprenNet, and Associated Press staff member Jim Gaines, who worked as a video software architect, the news organization confirmed.
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"This is an unthinkable tragedy. Rachel was a wonderful mother, daughter, sister, wife and friend. She was devoted to her family, her community and the pursuit of social justice. We cannot imagine life without her. We respectfully ask for privacy so that we can begin the process of grieving," the Jacobs family said in a statement on Wednesday.
Authorities were still trying to account for all people aboard the train and match the passenger manifest with records from the more than 200 people who were treated at area hospitals.
"We have made really good progress in accounting for the majority of individuals but we still have folks who we’d like to hear from," Philadelphia Director of Emergency Management Sam Phillips said during the briefing.
Nearly all patients admitted into Temple University Hospital sustained rib fractures from being bucked and tossed in the train cars, Dr. Herbert Cushing, chief medical officer said. As many as half of the 23 people remaining in the hospital's care were expected to be released later in the evening, while at least three more surgeries were scheduled for Thursday, he added. The patients' age ranged from mid-20s to a man in his 80s, with injured passengers hailing from across the globe, including Spain, Germany and India.
"In general we're doing much better," Cushing said. "Most patients' conditions are either stable or better, so that's very very good news."
Investigators with the NTSB arrived at the scene just before dawn to access the track, train signals, potential mechanical issues and human operation. “Our mission is to find out not only what happened but why it happened, so we can keep it from happening again,” Sumwalt told reporters. He said the NTSB's first priority is to recover "perishable evidence." Sumwalt also said an interview with the train's engineer will be conducted later, once he's had time to convalesce. In the meantime the NTSB will be interviewing passengers while the train cars will be examined in a secure location.
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Someone who knows the train's engineer told msnbc that Bostian is a cheerful guy and a rail buff. Asked whether he sensed any character issues with Bostian, the acquaintance said "not even in the slightest."
Pennsylvania Gov. Tom Wolf arrived at the scene of the wreckage just hours after the train jumped the tracks to survey the damage. He has since ordered American flags to be flown at half-staff throughout the state to honor those who died. Later in the day, Pennsylvania Sens. Bob Casey and Pat Toomey also visited the site and were updated in a full briefing.
House Transportation Committee Chairman Rep. Bud Shuster (R-Pa.) was set to travel to Philadelphia Thursday morning.
Amtrak board chairman Anthony Coscia was on the ground in Philadelphia Wednesday morning as the rail company set up a family assistance center for people to reunite with loved ones. “This is the Amtrak family," Coscia said at the press conference. "We are very saddened by what has occurred."
President Obama spoke with both Nutter and Wolf over the phone, White House Press Secretary Josh Earnest said, telling both men he was pleased with how local jurisdictions were handling the ongoing investigation. "Along the Northeast Corridor, Amtrak is a way of life for many," Obama said in a statement earlier. "From Washington, DC and Philadelphia to New York City and Boston, this is a tragedy that touches us all."
Vice President Joe Biden, an ardent supporter and regular Amtrak passenger throughout his career, said the derailment hit him personally. "The victims could have been any one of our parents, children, or someone from one of our communities. Amtrak is like a second family to me, as it is for so many other passengers," Biden said.
Witnesses described the chaotic scene — how the cars fell to their side, how passengers were flung around in their compartments, with some having to be lifted by safety by hydraulic tools. Hundreds of firefighters and police rushed to crash site to help survivors and help free several who were trapped in the train cars. Authorities declared the incident as a level-3, mass casualty event.
"Chairs inside the train became unscrewed and suitcases were falling on people," Max Helfman, 19, told NBC News. Helfman, who was heading home to New Jersey, added, "My mother flew into me and I literally had to catch her," he said. "People were bleeding from their head. It was awful."
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Former Congressman Patrick J. Murphy of Pennsylvania was also on board the train and tweeted chilling images of passengers being rescued by firefighters. “I’m on @Amtrak train that just crashed,” the Iraq war veteran tweeted. “Im ok. Helping others. Pray for those injured.”
He described the moment the train went off the tracks, telling msnbc's "Morning Joe," that he was sitting in the cafe car when “The train just literally rocked, like it buckled. It went to the left and shifted violently to the right and crashed to the side." He added that everyone on the left side of the train with him "just literally flew through the air and went to the other side.”
Amtrak services between New York and Philadelphia have been suspended, with schedules likely impacted by the investigation through Thursday. On "Morning Joe" early Wednesday, New York City Mayor Bill de Blasio estimated a $100 million impact on the economy every day the Amtrak Northeast corridor is shut down.
By sheer coincidence, the House Appropriations Committee held a previously scheduled meeting on Capitol Hill on Wednesday to address federal transportation funding. An amendment designed to fully fund Amtrak, however, failed in a 21-30 vote during the committee's markup hearing.
The crash has highlighted ongoing concerns about funding for national infrastructure, including railways and highways. A train derailed in a very similar fashion, in the same area, in 1943. The train was also traveling from Washington, D.C., to New York.
Those trying to contact passengers should call the Amtrak hotline at 1-800-523-9101.