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.

Related: Horned Bull on Penn Station Tracks Causes Commuter Delays

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.

Today is the @Amtrak trip from hell – asked to leave our Northeast Regional at Trenton after being stuck for hours, now on an NJ Transit. No idea how we get from Newark to NYC after if trains aren’t running. Customer service comms are horrible. How do we get made whole for this?

— Geoffrey M (@geoffmartello) June 20, 2024

@Amtrak needs to refund all passengers aboard Northeast Regional 85. Approaching two hours on a stopped, stifling train. Very poor communication.

— Mary O. Taber (@maryotaber) June 20, 2024

@Amtrak there is no way to get a refund for my cancelled train, not on your website nor via your call center. Will you give us our money back?

— Jenny Kroik (@jkroik) June 21, 2024

@NJTRANSIT You should refund people for the week long lack of trains into and out of NYC. You should also apologize, which I have yet to see. This week was a nightmare and the handling of it has been less than ideal. You are meant to be reliable and have been low on that bar.

— Kassandra (@Kassy976) June 21, 2024

If hell on Earth exists, it’s the NJTransit during a heat wave

— nickel (@nicole68864160) June 20, 2024

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.