An Amtrak train heading from New York to Savannah, Ga., struck a piece of construction equipment and derailed just south of Philadelphia, Amtrak says.
Two people died in the crash, Pennsylvania Emergency Management Agency authorities said at a press conference; neither were passengers or crew on the train. PEMA spokeswoman Ruth Miller says the two people who died were "in, on or near the backhoe that was struck."
Thirty-five passengers were hospitalized with non-life-threatening conditions.
Northeast Corridor service between Wilmington, Del., and Philadelphia was suspended for several hours.
Amtrak says the accident was caused when train 89 hit a backhoe on the tracks, derailing the lead engine. The railroad service says approximately 341 passengers and seven crew members were on board at the time.
Amtrak has established an emergency hotline; anyone with questions about friends or family who were on train 89 can call 800-532-9101.
Federal Railroad Administration investigators are on the scene, and The National Transportation Safety Board is en route.