ELKTON, Md. (CBS) — Amtrak has resumed train service between Washington, D.C. and Philadelphia after an earlier problem with overhead wires forced a suspension of service.

The extensive damage to overhead wires happened Wednesday in Cecil County, Maryland.

As a result, Amtrak suspended train service between Washington, D.C. and Philadelphia. An Amtrak spokesperson said it was not immediately known what caused the damage.

Service was restored at about 2 p.m. Wednesday.

Amtrak say passengers can expect extensive residual congestion delays through the area while crews complete the final repairs to the system and restore to the second available track to service.

Passengers who have paid, but choose not to travel due to this service disruption can receive a refund or a voucher for future travel. Some tickets booked online that have not yet been printed can be modified or canceled on Amtrak.com or by using the free Amtrak mobile app.