Sixteen railcars, including at least one carrying a hazardous material, came off the tracks in Whitemarsh Township early Monday.
Residents in the area were evacuated as a precaution, according to CBS.
Silicone pellets were leaking from at least one car. Police said they posed no risk to the public. It's not known what the others were carrying.
The 40-car CSX train was running on Norfolk Southern tracks when the derailment occurred.
The recent wet weather may be to blame. However, the investigation is continuing.
"While preliminary reports indicate that one car transporting hazardous material was involved in the incident, there is no indication of any leaks or spills of hazardous materials and there are no injuries to the crew of the train. The local fire department responded and declared an evacuation of just over a dozen homes out of an abundance of caution," CSX officials said in a statement.