Militants allied with the Islamic State group in eastern Congo killed at least 12 people in several villages in North Kivu province, a local official said Monday.

Fighters with the Allied Democratic Forces attacked people in the village of Mukonia on Saturday, the municipality's mayor, Nicole Kikuku, said on national television. The death toll might be higher because several villagers are still missing, the mayor added.

Attacks from the Allied Democratic Forces have increased recently. Last June, the group killed at least 40 people in several villages in North Kivu. It is also suspected of being behind a massacre last year when 41 people were killed, mostly students, in neighboring Uganda.

In 2021, Uganda's army launched joint air and artillery strikes against the ADF in eastern Congo.

Eastern Congo has struggled with armed violence for decades as more than 120 groups fight for power, land and valuable mineral resources, while others try to defend their communities. Some armed groups have been accused of mass killings.

The violence has displaced nearly 7 million people, many beyond the reach of aid.

The U.N. peacekeeping mission in Congo, which helped in the fight against rebels for more than two decades before being asked by the Congolese government to leave over its failure to end the conflict, will complete its withdrawal by the end of 2024. The three-phased withdrawal of the 15,000-member force has begun in South Kivu province.

The government also told an East African regional force, deployed last year to help end the fighting, to leave the country for similar reasons.