Suspected Allied Democratic Forces (ADF) militants have killed over 40 people in twin attacks in eastern DR Congo, local officials said Thursday, in the latest bloodshed across the turbulent region.

The ADF, which the Islamic State group claims as its central African affiliate, is one of the deadliest armed militias in eastern Congo, accused of slaughtering thousands of civilians.

Fighters from the group attacked the neighbouring villages of Mukondi and Mausa, in the Beni territory of North Kivu province, during Wednesday evening and the early hours of Thursday, officials said.

"It's total desolation," said Kalunga Meso, a local administrator. "They rounded up people and then executed them".

He told AFP that 38 people had been killed in Mukondi and eight in Mausa, stressing the death toll was provisional.

Mumbere Arsene, a local civil-society figure, said 37 people had been killed in Mukondi and eight in Mausa.

"All the dead people were killed with knives," he said.

The Kivu Security Tracker (KST), a respected violence monitor, said on Thursday that armed men had killed at least 30 people in Mukondi, by machete.

AFP was unable to independently confirm the death toll.

The ADF is among the most violent of the dozens of armed groups active in eastern Congo and has been accused of a string of bomb attacks and civilian massacres.

Thousands have died at its hands, many of them in the Beni region, say monitors.

A joint Congolese-Ugandan military operation targeting the militia in eastern DRC has been underway since late 2021, but attacks have continued.

Last week, the United States offered a reward of up to $5 million for information concerning ADF leader Seka Musa Baluku.

- Security Council visit -

The latest ADF attack comes as a United Nations Security Council delegation is due to arrive in the DRC on Thursday.

The envoys are due to visit conflict-torn North Kivu during their three-day visit, according to the official programme, in order to assess the security and humanitarian crisis.

Hundreds of thousands of people have been displaced inside the province, which besides suffering ADF attacks in its north, is also beset by M23 rebels.

The Tutsi-led M23 group has captured swathes of territory since re-emerging from dormancy in late 2021, and has recenty been gaining further ground on Congolese troops.

An M23 advance is now threatening to cut off all road links to Goma, a regional trade hub with Rwanda to its east and Lake Kivu to its south.

The DRC accuses Rwanda of backing the M23 -- an assessment the United States, several other western countries and independent UN experts agree with.

Kigali denies the charge.

Dozens of armed groups roam eastern DRC, many of which are a legacy of regional wars that flared in the 1990s and early 2000s.