UPDATE: Suspicious letter contained cellulose powder, deemed harmless

Suspicious mail investigation underway on Ripley St./Source: Alabama News Network

The Alabama Department of Corrections said the suspicious letter that was received Tuesday morning at the Criminal Justice Division downtown contained cellulose powder.

Cellulose power is considered harmless as it is used in food products and is the form for anti-caking applications.

ADOC says the department followed safety protocol and the building was cleared for normal operations at 2:30 p.m. While normal operations have resumed, ADOC says there are state and federal investigations still ongoing.

The Montgomery Fire Department, the Montgomery Police Department, the FBI and ALEA all responded to the scene. ADOC says the substance was identified by the National Guard Chemical, Biological, Radiological and Nuclear unit.