Pilgrim Station nuclear plant automatically shut down in the thick of the storm Friday night after losing power, according to a statement by Entergy, the plant's owner.
Authorities said there is no danger and backup diesel generators are powering safety systems.
"The plant is in a safe, secure condition and will remain on backup power supply until off-site power is restored," the statement said.
An unusual event is the lowest of four classifications of emergencies by the Nuclear Regulatory Commission.
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