The set of “NCIS” has been impacted by a mysterious malady that resulted in more than a dozen members of the cast and crew falling ill.

According to TMZ, at least 18 people working on the hit series came down with what’s described as “a sudden illness” on Thursday morning, with symptoms including vomiting.

A source claimed that the “mild symptoms” being experienced apparently indicated food poisoning, but there hasn’t yet been any confirmation of what’s caused the illness.

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When contacted by People, an “NCIS” executive had no comment.

In any case, the illness hasn’t affected filming, and the show has not halted production.

“NCIS” airs Tuesdays at 8 p.m. on Global.