JOHANNESBURG- Workers at China Molybdenum's Tenke Fungurume Mining (TFM) copper and cobalt mine in Democratic Republic of Congo went on strike on Saturday, demanding extra compensation for working on a site that has been isolated for two months due to COVID-19.

The Chinese mining firm placed the TFM mine in isolation from March 24 in a bid to protect the site from COVID-19. Essential staff were ordered to stay on site and forbidden from any contact with the outside world.

It was unclear how many mineworkers were on strike, and whether the mine was continuing to produce. A China Molybdenum spokesman did not immediately reply to a request for comment.

A document dated May 23 seen by Reuters listed TFM employees' demands, including an extra $100 a day per worker and contractor to compensate for working in isolation, and a bonus of $4,000 per person before they would return to work.

A video seen by Reuters showed a group of around 30 workers, in full protective personal equipment and face masks, singing together on the mine site.

Tenke Fungurume, one of Congo's biggest copper and cobalt mines, produced 117,956 tonnes of copper and 16,098 tonnes of cobalt in 2019.

China Moly projects the mine will produce between 163,000 and 200,000 tonnes of copper, and 14,000 to 17,000 tonnes of cobalt in 2020.

The governor of Lualaba province, where TFM is situated, was not immediately reachable for comment.

(Reporting by Helen Reid, additional reporting by Tom Daly in Beijing and Hereward Holland; Editing by David Evans) ((Helen.Reid@thomsonreuters.com; +27 11 595 2852;))