Part of an Amtrak train derailed Monday night in a narrow tunnel under Baltimore, halting much of the rail service between Baltimore and Washington.

No injuries were reported in the derailment, which occurred about 7 p.m. in the historic B&P tunnel that carries trains south of Baltimore’s Penn Station for about 11 / 2 miles.

However, late trains on MARC’s Penn Line commuter service between Baltimore and Washington were halted and Amtrak said its service between the two cities was also suspended. A MARC spokesman said buses were being provided for passengers whose trains stopped short of their destinations. Single-track service was restored by 9:30.

The train that derailed was Amtrak’s Silver Meteor, which runs between New York and Miami and was carrying 158 passengers, Amtrak said. The lead wheels of the locomotive left the tracks, but all passenger cars remained upright and on the rails. The cause of the derailment was not known.

The passenger rail service said electricity to the train was cut off for safety reasons, and a rescue locomotive was being sent to bring the passengers back to Penn Station.

The tunnel, which was built about 140 years ago, carries two tracks, and is regarded as a major bottleneck on the line connecting New York and Washington.