Two devices that appeared to be pipe bombs were found at separate post offices Tuesday, authorities said. Both buildings were evacuated and no injuries were reported.

Columbus bomb squads, the FBI, a U.S. Postal Service inspector, and local authorities were examining the devices found in Guysville and Stewart, two small towns in southeast Ohio.

It was not immediately clear if the devices were bombs, said Lisa Fitzpatrick, a Cincinnati-based postal inspector. Authorities in Guysville said the object there was considered safe, Fitzpatrick said.

Fire officials and the American Red Cross set up evacuation sites at a gas station in Guysville and at a high school in Stewart. Both towns each have fewer than 100 residents, said Athens County Planning Director Bob Eichenberg.

A contractor who delivers mail to the post offices discovered the devices and alerted the main office in Athens, The Athens Messenger reported on its Web site.

The contractor found the first device at the back door of the Guysville office and moved it slightly to make his delivery. It was about 1-foot long and appeared to have a transmitter. The second device was hanging on a side door of the Stewart office, the newspaper reported.

Postal service spokesman Ray Jacobs said postal employees are trained to isolate any suspicious item and not to touch it, but he didn't know whether a contractor would receive the same training.

Jacobs said mail delivery along the rural routes in Stewart and Guysville would be delayed until about noon. He said he would not speculate on why the devices were at the post offices.

"I'm sure it will be a while before the investigation uncovers why and who did it," he said.

Authorities have not commented on whether there may be any link to other explosives found Thursday at three sites in nearby Nelsonville, including one device that blew out the window of a camera shop. Three young men have been charged in those incidents.