An Arizona campaign office for Republican Senate candidate Kari Lake was forced to evacuate on Tuesday after a campaign staffer opened an envelope with a “suspicious” substance and a note that warned anthrax was present.

The incident occurred at one of Lake’s Phoenix offices with a note that said, “Caution anthrax,” according to reports. Lake’s campaign immediately notified local authorities. A hazmat team arrived with local law enforcement agencies and firefighters. Workers were evacuated from the building.