Ottawa ? Ottawa Police and U.S. Postal inspectors are awaiting test results on a suspicious white powder found early Wednesday the anniversary of the 9/11 terrorist attacks in an envelope at the Ottawa Post Office.

Postal inspector Tom Rebottaro with the U.S. Postal Inspection Service in Kansas City, Mo., said his office was notified shortly after 7 a.m. Wednesday that a white envelope that was not addressed or post marked and contained no written threat was found on the floor of the post office early Wednesday. There was powder inside the envelope and on the floor around it, he said.

A postal inspector was sent to the scene, and authorities Wednesday afternoon were awaiting test results on the powder, Rebottaro said.

He said the post office had been evacuated immediately and remained closed to the public Wednesday afternoon.

“Especially given the significance of today, we’re taking every precaution for the safety of our employees and our customers,” he said.