By: KDKA-TV News Staff

PITTSBURGH (KDKA) — The Department of Homeland Security is investigating a counterfeit N95 mask operation.

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Fake 3M masks were sold in at least five states to hospitals, medical facilities and government agencies.

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The 3M company is considered the gold standard for N95 masks.

The company’s website has tips on how to spot fakes – including tips on what to look for on the packaging and quality control.

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You can find that information by visiting this link.