Hazardous material teams ruled safe a suspicious letter that prompted the evacuation of Los Angeles Police Department headquarters on Thursday.
The letter, which contained a white powder, was mailed to the downtown headquarters and found in the facility's mail room around 8 p.m., the Los Angeles Police Department said via Twitter.
Most of those removed from the building were civilian staff members, officials said.
About two hours after the incident began, hazmat crews deemed the substance safe and allowed employees back into the building.
Surrounding streets would also reopen, LAPD said.
No further details were available.