A retired colonel who once supervised the modernization of the Air Force's computer network has been indicted along with the computer company doing the work, prosecutors said Friday.

Unisys Corp., and its predecessor, Sperry Corp., are each accused of falsely billing the government for more than $500,000 for work that was never performed, said U.S. Attorney Jim Wilson.Retired Air Force Col. Robert L. Hedges, 51, of Montgomery is accused of negotiating a consulting job with Sperry while he was overseeing the $526 million contract, said Wilson.

He said more indictments are expected from the three-year investigation. Hedges was indicted Wednesday and the companies on Tuesday.