KINSHASA, Congo (AP) — Militants from a shadowy extremist organization with ties to the Islamic State Group killed at least 14 farmers in Congo’s hard-hit eastern region, a local official said Saturday.

The Allied Democratic Forces attacked Mamove village in North Kivu province on Friday night where they beheaded the farmers working on their fields, said Samson Simara, a delegate of the provincial governor.

“This death toll could rise because other farmers are missing,” he told local media, adding that the militants also burned down several houses in the village.

Armed violence in eastern Congo has been simmering for decades as more than 120 groups fight for power, land and valuable mineral resources, while others try to defend their communities, but it spiked in late 2021 when another rebel group, that goes by M23 and had been largely dormant, resurfaced and initiated attacks to seize land.

The attacks have heightened tensions ahead of Congo’s presidential election in December, with many residents in affected communities afraid for their safety.

Congolese President Felix Tshisekedi, who seeks reelection, has said rebel-controlled territories might not participate in the December vote for security reasons.

The ADF has recently increased its attacks in Congo. The group is also suspected of being behind the June massacre where 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.