Updated at 7:33 p.m. ET
The Amtrak train that derailed Tuesday accelerated to more than 100 mph just before it entered the turn and the engineer then slammed on the brakes to slow it down, the National Transportation Safety Board said Thursday.
The derailment Tuesday night of Amtrak train No. 188 in Philadelphia killed eight people. More than 200 were injured.
NTSB board member Robert Sumwalt said at a news conference that the train's forward-facing camera showed that 65 seconds before the end of the recording, the train's speed was 70 mph; 43 seconds before the end, it was traveling at more than 80 mph. Thirty-one seconds before the recording stopped, the train was going at 90 mph, and 16 seconds before the end of the recording the train was traveling more than 100 mph, he said.
When the train entered the curve rated at 50 mph, it was going at 106 mph, he said. The engineer then applied the engineer-induced braking, slowing the vehicle down slightly to 102 mph in the moments before the crash, Sumwalt said, basing the numbers on the preliminary investigation.
"Just before entering the curve is when the engineer applied the engineer-induced braking to put it into emergency braking and I'll describe it as seconds, mere seconds into the turn, we could see the train tilting approximately 10 degrees to the right and then the recording went blank," Sumwalt said at the news conference.
He declined to say whether he considered that rate of acceleration rapid and added that it's unknown what caused the train to speed up.
He said the Amtrak engineer, who has been identified as Brandon Bostian, has agreed to be interviewed by investigators from the NTSB, which is looking into what caused the train to derail, killing eight people.
Sumwalt said that NTSB had released the Philadelphia accident site to Amtrak and moved all the train cars to a secure location in Delaware.
Meanwhile, at Camp David, Md., President Obama offered his condolences to the victims of the derailment and praised the work of first responders who helped rescue survivors.
He said that while it's too soon to tell what caused the accident, "We need to invest in infrastructure. ... That's what great countries do."
Earlier Thursday, Philadelphia Fire Commissioner Derrick J.V. Sawyer said that an eighth body was found by crews at the site of the derailment.
"We believe that we have now accounted for all 243 individuals that we believe were on Amtrak train No. 188 on Tuesday night," Philadelphia Mayor Michael Nutter said.
Sawyer said crews brought in specialized dogs Thursday morning that pinpointed one more body inside the wreckage of the first rail car. The crew was able to recover the body using heavy machinery.
During the same press conference, Joseph Boardman, the chief executive of Amtrak, said that because of the crash, the company will now install a safety mechanism across its entire Northeast Corridor.
"We're committed to meeting the requirement of positive train control and that will happen at the end of the year," said Boardman.
As we reported, positive train control, which automatically slows a train that's going too fast, has been mandated by federal law, but many railways are behind in implementation.
After Tuesday night's incident, safety advocates said a positive train control system could have prevented the crash. Investigators said train No. 188 was traveling at more than 100 mph entering a curve with a speed limit of 50 mph.
At an earlier press conference, Nutter called Bostian, the engineer on the train, "reckless and irresponsible."
Thursday, Nutter said he was not prejudging the outcome of the investigation. He said that what authorities know for sure is that the engineer was interviewed at a hospital and quickly said he did not want to be interviewed.
Robert Goggin, Bostian's lawyer, told ABC News that Bostian did not remember the incident, because he suffered a concussion and had 14 staples in his head.
ABC News adds:
"Goggin said that his client 'cooperated fully' with police, immediately consented to a blood test and surrendered his cellphone. He said he had not been drinking or doing drugs. Police had said on Wednesday that the engineer had refused to give a statement to law enforcement.
"Robert Sumwalt of the National Transportation Safety Board said on Wednesday that accident investigators want to talk to the engineer but will give him a day or two to recover from the shock of the accident. Goggin said his client was distraught when he learned of the devastation.
"The engineer hit the emergency brakes moments before the crash but slowed the train to only 102 mph by the time the locomotive's black box stopped recording data, according to Sumwalt. The speed limit just before the bend is 80 mph, he said."