Firefighters respond to SFSU Police Department after a university police officer was injured by an unknown chemical Thursday.

A San Francisco State University police officer was injured Thursday in an apparent chemical reaction as he was using a testing kit on an unknown substance found in a university-owned apartment.

“When the substances combined, it caused an unexpected reaction,” SFSU representative Ellen Griffin told the Golden Gate [X]press student news website.

The SF Appeal reports that the officer was briefly hospitalized, but four other officers who were nearby at the time of the chemical reaction were not hurt.

The incident began when officers responded to a report of a squatter at a university-owned apartment. No one was at the apartment when they arrived, but the officers confiscated some items found there, [Griffin] said. …

Griffin said the university will have an industrial hygienist investigate the incident and try to determine what the substance was.

Photo: Golden Gate [X]Press/Danielle Mitchell