DES MOINES, Iowa (AP) — A man convicted of killing his wife in western Iowa in 1982 has died in prison. The corrections department says 70-year-old Roy Bales died Tuesday at the Iowa Medical and Classification Center in Coralville. Department spokesman Fred Scaletta says Bales died as result of several health problems, including congestive heart failure. Bales was convicted of first-degree murder in Harrison County in August 1982 and sentenced to life in prison. Assistant County Attorney Judson Frisk says Bales was found guilty of killing his wife, Darlene. Frisk, who was county attorney at the time, says Bales beat up his wife and drove her to a country road where he stabbed her and hid the body in a tube under a gravel road.