PHILADELPHIA — An analysis by The Associated Press of surveillance video just before the deadly crash of an Amtrak train indicates it was traveling about 107 mph as it approached a curve where the speed limit is only 50 mph.

The death toll from the crash is now seven with the discovery of another body in the wreckage, authorities said.

The video shows the train — which was roughly 662 feet long — passes the camera in just over five seconds.

But AP found that the surveillance video inexplicably plays back slightly slower than in real time.

So, adjusting for the slower playback puts the train’s estimated speed at 107 mph. The surveillance camera is at a site just before the bend in the tracks.

More than 200 people were injured in the derailment that plunged screaming passengers into darkness and chaos Tuesday night.

Investigators recovered the locomotive’s data recorder and said they expected it to yield crucial information, including how fast the train was going when it jumped the tracks in an old industrial neighborhood not far from the Delaware River shortly after 9 p.m.

The engineer, who has not been identified, declined to provide a statement to authorities and had an attorney when he left a meeting with investigators, police said.

Mayor Michael Nutter said some people remained unaccounted for, though he cautioned that some passengers listed on the Amtrak manifest might not have boarded the train, while others might not have checked in with authorities.

The train was en route from Washington to New York with 238 passengers and five crew members listed aboard.