PHILADELPHIA (CBS) — Amtrak says Keystone Service is temporarily suspended for passengers traveling between Lancaster and Harrisburg, Pa., due to boulders blocking the tracks.

Amtrak says crews are working to clear the debris and resume service as quickly as possible, however, no alternate transportation is being provided.

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Passengers who have paid but choose not to travel due to this service disruption can receive a refund or a voucher for future travel.

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Some reservations booked online can be modified or canceled on Amtrak.com or by using the free Amtrak mobile app.

Passengers are encouraged to call 800-USA-RAIL or visit Amtrak.com/alerts for Service Alerts and Passenger Notices. Schedule information and train status updates are available at the Amtrak.com home page.

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