NEW YORK  — Amtrak and New Jersey Transit service on the Northeast Corridor in and out of New York Penn Station resumed Saturday after brief delays, but officials warned additional delays are possible.

Amtrak spokesman Mike Tolbert said earlier Saturday that train service in or out of the city was halted as crews investigated overhead power issues. Amtrak announced service was restored between New York and New Jersey after a delay of about 20 minutes.

Tolbert says there's no indication that this summer's track repair work at the nation's busiest rail station played a part in the delay.

Around 5 p.m. Saturday, a NJ Transit train with about 600 passengers became disabled near the tunnel causing another brief delay in and out of Penn Station. NJ Transit officials say service was restored in a half hour.

Amtrak's chief operations officer called the first week of summer-long track work and corresponding schedule cutbacks for commuters a success.

Crews are replacing aging equipment such as signals and several thousand feet of track over a two-month period.

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