The outage affected Amtrak trains as well as NJ Transit's Northeast Corridor, North Jersey Coast Line and Midtown Direct rail service in both directions.
Power was restored by about 11 a.m. but NJ Transit said that as of noon service on the Northeast Corridor and North Jersey Coast lines would be suspended, except for trains already en route to their destinations.
By about 1 p.m., the agency said service had been restored but with delays of up to an hour or more.
Midtown Direct service was still being diverted to Hoboken.
Passengers took to Twitter to describe conditions aboard the stalled trains, including trains stuck in the North River Tunnel beneath the Hudson River.
PATH and bus lines are cross-honoring tickets.
This story will be updated as more information becomes available.
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