Three people were taken to a hospital after an envelope containing a suspicious substance was opened at a government complex in Lebanon on Monday.
According to CBS affiliate WKRC-TV, police were called to the office on South East Street around 11:30 a.m.
The Warren County complex houses several offices including the Health and Human Services office.
Officials said a female worker opened a return envelope sent out as part of a questionnaire. When she did, her hands began burning.
Two other employees took her to a restroom to try and washed the substance off of her hands. All three of those workers were taken to a hospital, but only one remained Monday evening.
Authorities believe this was not an act of terrorism but a household chemical in the envelope.
The building should be ready to reopen on Tuesday. The FBI was called to the scene to investigate.
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