M23 fighters and Rwandan troops entered the DR Congo provincial capital of Bukavu on Friday, security and humanitarian sources said.

M23 now controls nearly all of North Kivu and the province’s vast mineral wealth—including tin (cassiterite), tantalum (coltan), tungsten (wolframite), and gold, which are critical for global electronics and industrial production.

Rwanda-backed rebels in eastern Congo have claimed that they have seized a second airport in the region following a days-long advance towards Bukavu city. Meanwhile the U.N. warned that the

Rwanda-backed rebels in eastern Congo entered the region’s second-largest city of Bukavu on Friday, local and civil society leaders said, the latest ground gained since a major escalation of their yearslong fighting with government forces.