WALDWICK, N.J. (AP) -- Hundreds of utility customers in Bergen County lost power after an explosion at a substation sent flames and thick, black smoke shooting skyward.

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It wasn't immediately clear what caused the explosion in Waldwick, which was reported around 10:40 a.m. Sunday.

The Record reported that several nearby homes were evacuated as a precaution, but no injuries were reported.

Officials say about 2,000 customers lost their service for a few hours, but power was mostly restored by early Sunday afternoon. A utility spokeswoman said the incident remains under investigation, and Waldwick police declined comment.

Firefighters from Waldwick and several nearby towns were battling the blaze, which was still burning late Sunday afternoon.

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