MARTINEZ -- A Concord man pleaded guilty to voluntary manslaughter Wednesday afternoon in the stabbing death of a neighborhood acquaintance, according to Contra Costa Deputy District Attorney Mary Knox.

Joshua Cardone, 22, was sentenced to 12 years in prison, Knox said.

Cardone was charged in the April 3, 2011, death of Richard Gilliam, 20, who was killed outside a fast-food restaurant in the Clayton Valley Shopping Center on Ygnacio Valley Road in Concord. Investigators believed the stabbing was the result of a dispute between the two men.

Contact Gary Peterson at 925-952-5053. Follow him at Twitter.com/garyscribe.