“Vials labeled as smallpox were discovered at a Pennsylvania lab, the Centers for Disease Control and Prevention said Wednesday.

“The Frozen Vials “were incidentally discovered by a laboratory worker while cleaning out a freezer in a facility that conducts vaccine research in Pennsylvania,” a CDC spokesperson said in a statement to NBC News.

“The contents appeared to be intact, and the CDC is partnering with law enforcement to investigate, the agency said.

““The laboratory worker who discovered the vials was wearing gloves and a face mask. There is no indication that anyone has been exposed to the small number of frozen vials. We will provide further details as they are available,” the spokesperson said.”

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