Services are temporarily suspended due to overhead wires being down on a train just outside Philadelphia's 30th Street Station.
Officials said there are approximately 150 passengers on board the train, but said they are not in danger.
SEPTA is currently coordinating with Amtrak to ground the wires and make repairs.
Officials said once it is safe, they will evacuate the passangers and accommodate them with buses.
SEPTA said they are working to restore services as soon as possible.