U.S. Customs office in Alameda, California, evacuated over envelope with suspicious substance

A federal building in the San Francisco Bay Area received an envelope with a suspicious substance inside it, causing three people to fall ill.

The letter caused the evacuation of the U.S. Customs and Border Protection office in Alameda and the quarantining of more than two dozen workers, according to multiple San Francisco area news outlets.

“Hazmat teams, as well as firefighters and ambulances [are] on scene. Dozens of other people were seen standing outside the building inside an area roped off with police tape,” reported TV station KTVU.

KTVU said the illnesses seemed like allergenic reactions.

There was no immediate claim of responsibility or any statements from officials about whether the letter stated the sender’s motive.