Churchill Downs Inc. says it has completed the purchase of a Maine casino in a deal valued at about $160 million. The Louisville-based company said Wednesday its acquisition of Oxford Casino won approval from the Maine Gambling Control Board. Oxford Casino opened in 2012 and is situated about 40 miles northwest of Portland in Oxford, Maine. The property includes a 25,000-square-foot gaming floor with 790 slot machines and 22 table games. It also includes a restaurant. The acquisition is Churchill’s latest venture into the casino business. It owns racetrack and casino operations in Miami Gardens, Fla., and New Orleans: a casino resort in Greenville, Miss.: and a casino resort hotel in Vicksburg, Miss. Churchill also owns and operates its namesake racetrack that’s home to the Kentucky Derby, along with racetrack operations in Arlington Heights, Ill.