Revel casino lost money when it fell off roof

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Atlantic City's Revel casino, which announced earlier this month that it will soon shutter, lost more than $20,000 in cash when the money fell off the roof of an armored truck, according to a report from Press of Atlantic City.

An investigation is underway after Boston-based GardaWorld armored car services told the casino on Aug. 6 that it had lost $21,000, Press of Atlantic City wrote, citing an incident report.

Read More Revel Casino says closure will help it find a buyer

The report said the cash was left on the roof, and that surveillance video from another casino shows the bag still on the vehicle during a subsequent pickup. The news report said that it "is not clear where or when the money fell off."

"We are cooperating with the authorities in investigating this incident and cannot provide any additional details," Joe Gavaghan, GardaWorld director of corporate communications, told Press of Atlantic City.

-By CNBC staff

Read More Atlantic City's Revel Casino to close in September

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