We previously reported that 22 samples of live anthrax were accidentally sent to labs in nine states and a U.S. base in South Korea. Since the news came to light, Department of Defense investigators have put their heads together to figure out how this disaster occurred and pinpoint who is responsible.

Instead, the plot has thickened. Officials announced Tuesday that a lab in the Pentagon has also mistakenly received live anthrax samples. When a location as secure and central as the Pentagon starts accidentally getting anthrax in the mail, we all have reason to open our packages more carefully.

The Pentagon uses inactive anthrax to calibrate their biological threat sensors. This helps keep the entire facility and the people who work there safe from potentially poisonous mail and other biological attacks. The irony is not lost on us.

A U.S. defense official told MilitaryTimes.com that the anthrax was received on Pentagon property, but did not make it inside the building.

Earlier the same day, the Pentagon stated that the anthrax originated from the Army’s Dugway Proving Ground in Utah. The samples were supposedly rendered inactive before sending to other research labs, but they were very much alive and kicking when researchers received the packages.

The samples were mailed over the course of a year. Most of them have either been unopened and frozen, and there is no risk to public safety.

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