The FBI and the Department of Homeland Security are helping local authorities in Sacramento after the University of California, Davis, police reportedly received a threatening letter from someone claiming the campus water supply was tainted.
UC Davis public information officer Sylvia Wright later told KCRA-3 that the school received a non-threatening letter that said someone dumped a half bottle of Armor All, a cleaning product for cars, into a campus well.
She also said an overzealous groundskeeper heard about the letter and put up signs around the Sacramento campus on his own.
University officials said they have run some tests, and the water comes back clean, with no problems.
Homeland Security officials were called to investigate, but the university says it's merely a hoax.