Amtrak service was suspended between Philadelphia and New Haven, Connecticut, on Thursday afternoon as crews try to restore power in the New York area, Amtrak said.
The outage includes trains in and out of New York Penn Station, Amtrak said.
New Jersey Transit said its trains are also suspended in and out of New York Penn Station.
The outage was reported shortly after Amtrak warned that the extreme heat in the Northeast might force trains to slow down, causing up to one-hour delays. It was not immediately clear if the service suspension was caused by the heat.
This is a developing story. Please check back for updates.