NAIROBI , Kenya ( CNN ) -- The deaths of 26 victims in the latest wave of violence in the Democratic Republic of the Congo might constitute war crimes , a United Nations spokesman said Saturday . A Congolese girl cries as she walks with her mother near Kibati on Friday . It is unclear who was responsible for the deaths in the village of Kiwanja or how many of the victims were civilians . But if some of the victims are found to be non-combatants , their deaths could be handled by a war crimes tribunal , said Madnodje Mounoubai , U.N. mission spokesman in Kinshasa . `` Some were combatants , and some were not , '' he said . `` If it is determined that they were not just caught in the crossfire -- that they were pulled out of their homes or singled out for questioning and killed -- that would make it a war crime . '' Mounoubai made the remarks one day after leaders at a regional summit called for an immediate cease-fire and the creation of humanitarian corridors in areas plagued by bloody attacks . Fighting broke out at the end of August between the Congolese army and rebel forces led by Gen. Laurent Nkunda . Despite a unilateral cease-fire declared by Nkunda last week , fighting has continued , and there are reports of heavy civilian casualties in recent days . Mounoubai also said that a U.N. team in Kiwanja had confirmed reports of 26 bodies in 11 graves in the village . Residents told the U.N. team that rebels killed the victims amid accusations that they collaborated with government troops , Mounoubai said . In a communique released at the end of Friday 's African Union-hosted summit , regional leaders asked for a strengthening of the mandate for peacekeeping forces in the country . There are 17,000 U.N. peacekeepers in Congo , the largest U.N. peacekeeping force in the world , but U.N. Secretary-General Ban Ki-moon said the forces have been `` stretched to the limit . '' He said Friday that the recent violence , which the United Nations estimates has displaced 252,000 people , must be prevented from spilling into the wider region . `` Neither the DRC nor Rwanda nor the rest of the Central Africa region can afford to be dragged back into conflict . The international community can not allow this to occur , '' Ban told the leaders . `` For far too long , peace and security in your region has been threatened by armed groups , domestic and foreign , present on the soil of the Democratic Republic of the Congo . They have been operating from there with impunity , aggravating strains between your countries and between your peoples . '' The fighting has aggravated an already serious humanitarian crisis , the United Nations and aid groups say . Nkunda was not present at the summit . Congolese President Joseph Kabila and the presidents of Congo 's neighboring countries -- Paul Kagame of Rwanda , Jakaya Kikwete of Tanzania , and Yoweri Kaguta Museveni of Uganda -- were among the leaders there . Ban implored the leaders to use their influence in restoring stability to eastern Congo . `` As leaders of Africa , you have a historic responsibility . This is a critical moment for the Great Lakes region and for Africa as a whole . We must put the cycle of violence behind us , '' he said . `` We must build a shared future of stability , peace , development and human rights for all citizens of your countries . '' In particular , Ban said , they should urge Nkunda not to resume fighting , prevent him from getting support and urge him to pull back his rebels . Human Rights Watch reported Thursday that Nkunda 's rebel forces and the opposing government-backed Mai Mai militias deliberately killed civilians in Kiwanja , in North Kivu , on Tuesday and Wednesday in violation of Nkunda 's declared cease-fire . `` Eyewitnesses in Kiwanja told Human Rights Watch that at least 20 persons were killed and another 33 wounded during a battle for the town and in the cleanup operations by Nkunda 's forces that followed , '' the group said in a written statement . Nkunda denied Thursday that his soldiers were involved in any civilian killings and said the Mai Mai were dressed in civilian clothing . `` These Mai Mai , these militia were in civil dress . ... We asked the civilian population to get behind the front lines . So , the population were behind the front line , '' he said . `` We can not kill a civil population . '' Human Rights Watch said U.N. peacekeepers in the area were unable to protect civilians . After the rebels re-established control of Kiwanja on Wednesday , Human Rights Watch said , they ordered all 30,000 residents of the town to leave . They then sought out and killed civilians , particularly men , whom they accused of supporting their enemies , the groups said . `` People in Kiwanja said they heard screams into the night and saw bodies on the streets the following morning , '' Human Rights Watch said . One of those killed was a journalist working for a local radio station , the group said . Witnesses said Mai Mai militias targeted civilians in Kiwanja , including those they accused of supporting Nkunda 's forces , Human Rights Watch said . The conflict in Congo is complicated by outside forces and a variety of armed groups fighting both the government and each other . Some analysts say Rwanda is Nkunda 's principal supporter . Rwanda denies that . For several years , it has called for the disarming of Rwandan Hutu rebels , many of whom are in eastern Congo .
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