Truck Accident GraphicPhiladelphia, PA- The death toll from last night’s passenger train accident rose Wednesday afternoon as federal investigators began looking into the cause of the disastrous crash that injured well over a 100 people.

The accident occurred Tuesday night as Amtrak No. 188 was traveling from New York to Washington D.C. After making a stop in Philadelphia the train continued on its normal route until it reached the Port Richmond area where something went wrong, causing the train to derail. According to NBC News, all seven of the train’s cars came of the track– some saw–flew, with several of the cars overturning.

The latest casualty of the train derailment was announced Wednesday just before 1 p.m., bringing the death toll to seven, which authorities say could continue to rise as the wreckage is cleared. At least five people were killed in the initial collision and the sixth person died earlier Wednesday at the hospital.

Over 140 of the estimated 238 passengers were taken to local hospitals for treatment. At least eight people are listed in critical condition.

Witness said luggage and objects flew around and many had to crawl out of cars that were completely or partially on their sides. Those at the scene describe the wreckage as “mangled” and “twisted” and say that the engine car took the brunt of the impact.

The identities of the all deceased victims have not been confirmed or released from authorities. The Associated Press reported that one of their employees, 48-year-old Jim Gaines, a software architect. The other victim is 20-year-old Justin Zemser, a U.S. Naval Academy Midshipman from Rockaway Beach, New York, according to Philly Voice. , and Associated Press software architect Jim Gaines, 48, of Plainsboro, New Jersey, are among the dead, according to media reports.

Philadelphia Mayor Michael Nutter said some passengers thought to be on the train are still missing. They are asking any passengers who were on the train and are fine contact officials

“We walked the entire length of the train area. The engine [is] completely separated from the rest of the train and one of the cars is perpendicular to the rest of the cars. It’s unbelievable,” Mayor Nutter told reporters in a press conference following the crash.

Investigators from the NTSB are on the scene and have already retrieved the train’s black box.  NBC News reports that in the area where the accident occurred, the speed limit drops from 70 mph to 55 mph as the rails go into curve, so investigators are looking at speed as a cause. CNN’s Brooke Baldwin reports that the train was going over 100 mph when the train derailed, but other factors could be at play. Investigators will also be looking at the condition of the tracks, the train’s brakes and wheels and any other mechanical issues.

Passenger trains between New York and Philadelphia have been suspended until the derailment can be cleared, but that could be a couple of days.

In any accident, whether it was a truck or, in this case, a train accident, knowing the cause is crucial and affects any final settlement amounts a victim receives. Accident victims who wish to seek compensation for their medical bills or loss of a loved one need to speak with a truck accident attorney immediately.  USAttorneys can refer you to a skilled personal injury attorney who specializes in car, train or truck accidents in your area to help you file your wrongful death or personal injury claim.