KINSHASA, Jan. 30 (Xinhua) -- At least 200 miners were killed after several mine shafts collapsed at coltan sites in Rubaya of the eastern Democratic Republic of the Congo, a spokesperson for the March 23 Movement rebel group confirmed on Friday.

Most of the victims were artisanal miners who were buried, the spokesperson said, adding that children and women were also among the dead.

The collapses occurred on Wednesday and Thursday at different coltan mines in Rubaya, an area controlled by the rebels since April 2024.

Coltan, or columbite-tantalite, is the main source of tantalum, a rare metal used in the production of advanced electronic devices. The United Nations estimated that the Rubaya mines alone account for about 15 percent of the global tantalum supply. ■