A 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 on Thursday.

A spokesperson for the March 23 rebel group (M23) said the town was “liberated.”

The Congolese army declined to comment.

The decades-long conflict in eastern Congo has produced one of the world’s worst humanitarian crises, with more than 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 seven 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 through its supply chain.

Ernest Singoma, a civil society activist in Goma, said: “The fall of Rubaya is in a way the embodiment of this systemic plundering.” 

There’s been an upsurge in fighting in recent months between M23 rebels and Congo army forces, and it comes as the United Nations plans to withdraw peacekeepers from the region by the end of the year.

Civil society activist John Banyene, said the rebels were advancing towards the town of Goma, which is eastern Congo’s largest city and the capital of North Kivu province.

“All the supply routes to the city are blocked,” said Banyene. “We are just getting by.”

Congolese President Felix Tshisekedi alleges that Rwanda is destabilising Congo by backing the M23 rebels.

United Nations experts have also accused Rwanda of backing the rebels. Rwanda denies the claims.