A white South Carolina restaurant manager has pleaded guilty to abusing and enslaving a mentally challenged black employee.

The U.S. Department of Justice says Bobby Paul Edwards of Conway pleaded guilty Monday to one count of forced labor. Prosecutors say Edwards admitted using violence, threats, isolation and intimidation to compel a man with an intellectual disability to work for more than 100 hours a week without pay.

Authorities have said Edwards used force and threats to force John Christopher Smith to work as a J&J Cafeteria cook from 2009 until 2014. Court documents describe beatings with a belt, choking, slapping, punching with a closed fist and burning with tongs used in hot grease.

Edwards faces up to 20 years in prison when he's sentenced later.