In the eastern Democratic Republic of Congo, more than 200 people were killed after heavy rains triggered a landslide at a major coltan mining site. About 70 children were reportedly among the victims. The Rubaya mines are controlled by the M23 rebel group, which disputed the government’s death toll, claiming there had been a bombing at the mining site and that only five people were killed. Al Jazeera reports the Rubaya mine produces about 15% of the world’s coltan, an essential metal that is processed into tantalum to manufacture smartphones, electric car batteries and other devices. Child labor is rife at the mines, with workers facing what has been described as modern-day slavery conditions.