More than two dozen people have been killed in two separate attacks in eastern DR Congo, a region in the grip of militia violence, officials said Wednesday.

"CODECO assailants attacked the people of the village of Koli while they were asleep, killing 22 civilians," said Adel Alingi, head of the Djugu administrative region in Ituri province, referring to an armed group targeting the Hema ethnic community.

The raid took place overnight Saturday-Sunday. "All (of the dead) were from the Hema community," Alingi told AFP, adding that the motive for the attack remained unclear. "The people of the village have fled for their lives," he said.

In the second attack on Tuesday, two soldiers, a civilian and five members of the Allied Democratic Forces (ADF) militia were killed in Beni, in neighbouring North Kivu province, the army's regional spokesman, Anthony Mualushayi, told AFP.

CODECO -- whose official name is Cooperative for the Development of Congo -- is an armed political-religious sect in Ituri drawn from the Lendu ethnic group. Conflict between the Lendu, mainly farmers, and the Hema, herders and traders, has a long history in the gold- and oil-rich province.

Tens of thousands were killed between 1999 and 2003. According to the UN, most victims were targeted because they were Hema. The conflict has reignited in recent years. More than than 700 people have been killed in Ituri since late 2017, a UN report said in January, adding that some of deaths might constitute a "crime against humanity."

The ADF began as an Islamist-rooted rebel group in Uganda that opposed President Yoweri Museveni. It then fell back to North Kivu, DR Congo's border province with Uganda, during the Congo Wars of the 1990s. Since October 2014, the group has been accused of killing more than 1,000 civilians.

Hundreds died in bloodletting that began last October, in apparent reprisal for an army offensive against the ADF. The army has claimed a string of successes, saying it has "destroyed all the ADF strongholds" in the forest and jungle around Beni, and killed five of six known rebel leaders.