At least 28 people were killed in north-eastern Democratic Republic of Congo in the past two days, the UN mission MONUSCO said.
A series of attacks in north-eastern Congo targeted civilians, including children, fleeing a resurgence in recent months of ethnic clashes between farming and herding communities.
MONUSCO said in a statement that assailants had attacked people in displacement camps and villages across Ituri province, including near one of its temporary bases.
Since early June, violence has killed over 200 people and displaced another 300,000.
The attacks in Ituri have mostly targeted Hema herders, who have long been in conflict with Lendu farmers over grazing rights and political representation, although the exact identity of the assailants remains murky.
Open conflict between Hema and Lendu from 1999-2007 resulted in an estimated 50,000 deaths in one of the bloodiest chapters of a civil war in eastern Congo that left millions dead from conflict, hunger and disease.
Tit-for-tat attacks between the two groups in late 2017 and early 2018 killed hundreds of people and forced tens of thousands more to flee their homes, but a tenuous calm had taken hold until last June.
Congo President Felix Tshisekedi, elected in January, is trying to restore stability to the country’s eastern regions, where armed groups clash over ethnicity, natural resources and political power.
Several militia leaders surrendered, been captured or killed during his first months in office. But armed violence has persisted, particularly in North Kivu province, south of Ituri, which is also the epicentre of a 10-month Ebola outbreak.