Stores Across the Country Hit With Wave of Bomb Threats From Scammers Demanding Bitcoin and Gift CardsLaw enforcement officials are investigating the recent threats.

Scammers are coming for large retailers across the county.

Since earlier this year, stores likeTarget,Walmart,Kroger,Whole Foods Marketand more have been the target of bomb threats from callers threatening to detonate alleged bombs in the stores if they don't receive payment ofBitcoin, gift cards or money, authorities told theWall Street Journal. Stores from New Mexico to Wisconsin have been affected by such threats, and local law enforcement agencies are investigating the incidents.

Bomb threats demanding ransoms are "unusual," according to the outlet, and appear to be a new form of extortion targeting retailers.

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In one instance, a caller demanded $5,000 in Bitcoin from a Whole Foods Market employee in a Chicago suburb, stating they had placed a pipe bombin the store, theWSJreported. A Kroger in New Mexico received a call demanding it wire money, and if employees called the police a bomb would go off. In both cases, authorities were notified and evacuated the buildings but found no suspicious items.

尽管美国联邦调查局正与当地和国家law enforcement officials, police say the scammers have been hard to track down as they're calling from blocked numbers. It's unclear if the calls are connected by a larger organized effort. Law enforcement officials noted that the targeted stores seem to only be threatened once, with no repeat callers.

Officials advise people to take the calls seriously, not to give away any payments and to try to extract as much information as possible from the callers.

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Although the calls started earlier this year, they increased in the spring, according to Doug Baker, vice president of industry relations at the food trade group FMI. "It's disruptive," Baker told theWSJ, "If I'm a retailer…I've gotta close stores and have to call law enforcement. And send customers out."

Many of the targeted stores have issued memos informing staffers of bomb threat protocols and are cooperating with law enforcement in the investigation.