A court in China's far-western Xinjiang Uygur Autonomous Region on Saturday sentenced a couple, who owned a building materials factory, to prison, for enslaving mentally ill workers and forcing them to work without pay.

Li Xinglin, owner of the Jiaersi Green Construction Material Chemical Factory in Toksun County, was sentenced to four years and six months in prison. Li Yunhua, the wife, was given a two-year term with a three-year reprieve.

Each of them was given a 50,000 yuan (about 7,657 U.S. dollars) fine.

The couple was convicted on Saturday of crimes of forcing employees to work and negligently causing serious accidents, according to the court.

Police said that the couple had enslaved 18 mentally handicapped workers from 2006 to December last year, forcing them to work in bitter environment, without protective gear and pay.

The couple said on Saturday that they would not file an appeal.