Sheriff Tommy Boswell told the Columbus Ledger-Enquirer that jail officials could not located the key Saturday and locked the jail down as a precaution.
Boswell said one of the guards could not locate a key.
He said that doesn't happen ofter, but said occasionally a guard may accidentally take a key home.
He said when that happens, inmates are kept in their cells during the lock down.
The jail was also closed to visitors.
Funds for a new locking and computer system at the jail were recently approved by the Russell County Board of Commissioners.
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