The Democratic Republic of Congo’s government has sent former warlords to try resolve the conflict in their home region of Ituri.
Last week, the delegation including Germaine Katanga and Mathieu Ngudjolo arrived in Ituri, which has been an epicentre of conflict in the country for many years.
Katanga was charged and convicted by the International Criminal Court in 2014 for being an accessory to four counts of war crimes and one crime against humanity, including complicity for a 2003 attack that killed more than 200 people.
Ngudjolo was prosecuted but acquitted by the ICC for alleged roles in the same attack.
The use of "converted" former militia leaders as peace messengers was part of DR Congo President Felix Tshisekedi campaign promises.
Katanga was released from prison on 16 March under an agreement with the government to promote peace and reconciliation in Ituri.
Meanwhile, gunmen killed 11 people in Ituri including military and local officials in an ambush attributed to CODECO, a militia accused of a string of massacres, AFP reported on Sunday.
"The death toll is 11, including the deputy territorial administrator in charge of economy and finance, three policemen and four soldiers," Djugu territory administrator, Adel Alingi Mokuba, was quoted as saying.
More than 500 civilians have been killed by armed groups in Ituri since October, according to the UN.
The UN has already warned that the attacks “may amount to crimes against humanity and war crimes”.