AKRON, Ohio (WJW) — The Akron Federal Building was cleared, and those evacuated within the block nearby were able to return Wednesday after a bomb threat was deemed not credible.

Akron Fire Chief Joseph Natko described the incident as “quite a large threat that we faced.”

Natko said authorities received a call at about 9:44 a.m. after a white powder substance was found in the mailroom. Hazmat crews responded and determined it was not a dangerous substance.

Shortly after the substance was found, a note was found that said there was a bomb in the building. At that time, the building was then searched for an explosive device.

A device was not found.

Officials believe the bomb threat was made by the same person who sent the substance to the building. Authorities originally reported that the threat was verbal.

Hazmat officials are still working to determine what the substance was.

There is no suspect information, and the incident is still under investigation.