The mall also said it was "assessing" the situation and may reopen later today, but in a subsequent statement said it would remain closed Monday. The mall is expected to reopen on time Tuesday.
Messages for mall management were not immediately returned. A spokesperson for the Millburn police department was not immediately available.
A staffer at the mall said a manager was speaking to the fire marshal regarding the situation.
Photos on social media show areas of the mall under a few inches of water.
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