NASHVILLE, Tenn. -- All Tennessee prisons, including Riverbend in Nashville, have been put on alert Thursday night. That's because prison officials are looking into who tried to smuggle loaded guns into an east Tennessee prison. They tried to do it using the U.S. mail, the library and a board game.

Video: Guns Found In Checkers Game

Two extra pieces in a checkers board game concerned the Department of Correction, said Commissioner George Little.

"One was a .25-caliber automatic pistol with full clip," he said.

The guns were packed with books in a box addressed to the library at the Morgan County Correction Complex near Knoxville. Mail for the prison is picked up at the U.S. Postal Service.

The guns never made it past security, as prison guards discovered them as they went through an X-ray.

"We screen all mail … drugs … items,” said Little.

Prison officials said it has been many years since they’ve had an incident like this. They said that guns getting inside a prison is not that common, though they do confiscate parts of guns from time to time.

There is currently a new addition being added to the Morgan County facility that will make it the most secure prison in the state once it’s completed.