A travel nightmare for commuters struck the Northeast on Thursday as power issues related to a heat wave caused significant delays and closures for New Jersey Transit and Amtrak trains.

Issues with both transportation services plagued commuters and travelers at New York’s Penn Station, the busiest transit hub in the Western Hemisphere which sees over 600,000 passengers pass through daily.

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Early Friday morning, NJ Transit told customers that rail service in and out of New York’s Penn Station was suspended due to “AMTRAK overhead wire issues” and that all tickets were being cross-honored by NJ Transit buses and PATH Trains (a separate train service that runs between Manhattan and parts of New Jersey, including Hoboken and Jersey City).

Around 10:45 a.m., NJ Transit said that services had resumed but train times were subject to 45-minute delays.

Issues first arose after Amtrak reported an overhead power outage just before 2:45 p.m. on Thursday and warned passengers of potential delays between New York Penn in Manhattan and Newark Penn Station in New Jersey. A couple of hours later, Amtrak reported that service along the Eastern corridor between New Haven, Connecticut and Philadelphia was suspended as a result of the power outages and an unrelated brush fire in New Jersey.

Early Friday morning, Amtrak also canceled two Acela trains. Commuters took to social media demanding refunds or answers for trains that had either been canceled or delayed significantly.

The Northeast is currently facing an excessive heat wave, with temperatures in mid 90s, which can cause power lines to sag.

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The root cause of the issue was a broken circuit breaker which caused power outages out on the tracks of different trains, Amtrak said.

This is a developing story.

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