COLUMBUS (WCMH) — Hazmat crews were called to Columbus Police Headquarters today after a white powder was found in an envelope. Officials later determined the substance was not hazardous.

According to the Columbus Division of Fire, crews were called to the headquarters at about 4:50pm, Monday on the report of a possible hazardous material found in an envelope. When firefighters arrived on scene, they say a white powder was found.

According to the Columbus Division of Police, a threatening letter was found with the powder. Headquarters was then closed until further notice while crews investigated.Keep checking NBC4i.com for real-time updates on this story. To get alerts for breaking news, grab the free NBC4 News App for iPhone or Android. You can also sign up for email alerts.