A pastor and his wife have been arrested in South Africa after 200 people, some in chains, were found held at a suspected illegal rehabilitation centre in the north-eastern part of the country.

The facility, operated from a church in Mpumalanga province, was discovered during an operation by officials in the area on Thursday.

Authorities said they uncovered “gross inhumane conditions” when they raided the facility, with some patients found with “sores all over their bodies” and “others chained to each other”.

Police have since charged the couple, who were running the facility, with kidnapping but could add more charges. They have not yet commented.

Illegal rehabilitation centres have mushroomed in South Africa in recent years as drug use spirals in the country.

Last year, the department of social development said it had uncovered over 100 unlawful facilities operating across the country, mostly in Gauteng province.

This is where some of those found at this facility come from, the department said in a statement on Friday.