A rebel group with alleged links to Rwanda this week seized Rubaya, a mining town in eastern Congo known for producing a key mineral used in smartphones, the group said Thursday in a statement...

The decadeslong conflict in eastern Congo has produced one of the world’s worst humanitarian crises, with over 100 armed groups fighting for control of the mineral-rich area near the border with Rwanda. Many groups are accused of carrying out mass killings, rapes and other human rights violations. The violence has displaced about 7 million people, many beyond the reach of aid.

The town of Rubaya holds deposits of tantalum, which is extracted from coltan, a key component in the production of smartphones. It is among the minerals that was named earlier this month in a letter from Congo’s government questioning Apple about the tech company’s knowledge of “blood minerals” being smuggled in its supply chain...

"The fall of Rubaya is in a way the embodiment of this systemic plundering" ...[says] a civil society activist in Goma...

Congolese President Felix Tshisekedi alleges Rwanda is destabilizing Congo by backing the M23 rebels. U.N. experts, along with the U.S. State Department, have also accused Rwanda of backing the rebels. Rwanda denies the claims.

Earlier this week, French President Emmanuel Macron called on neighboring Rwanda to halt its support for the M23 rebel group during a joint press conference with Tshisekedi in Paris.

Onesphore Sematumba, an analyst with the International Crisis Group, said the capture of Rubaya was a significant development in the conflict. “Rubaya has mining deposits and without doubt this will allow M23 to exploit them,” he told the AP.

The March 23 Movement, or M23, is a rebel military group mainly made up of ethnic Tutsis that broke away from the Congolese army just over a decade ago. They staged a large offensive in 2012 and took over the provincial capital of Goma near the border with Rwanda, the same city they are threatening again.