United Nations, Aug 1 : UN Secretary-General Antonio Guterres has expressed outrage after UN peacekeepers opened fire and killed two residents of a town in Democratic Republic of the Congo (DRC) that borders Uganda. In Kasindi, North Kivu province, military personnel of the UN Organization Stabilization Mission in the DRC (MONUSCO) opened fire at residents on Sunday, reports Xinhua news agency. In addition to the two deaths, 15 others were injured in the deadly incident, said the DRC government, which strongly condemned the shooting. "The Secretary-General is both saddened and dismayed by the loss of life and serious injuries sustained during this incident," Guterres' deputy spokesman Farhan Haq said in a statement late Sunday. Moreover, Guterres conveyed his deepest condolences to the victims' families, the Congolese people and the Congolese government and wished the injured a speedy recovery. Furthermore, the Secretary-General emphasized the need to "establish accountability for these events." The UN has established contact with the peacekeepers' country of origin, with the aim of "urgently initiating judicial proceedings with the participation of victims and witnesses so that appropriate sanctions can be handed down", the statement said. In a communique, the Special Representative of the UN Secretary-General in the DRC and head of MONUSCO Bintou Keita said that some soldiers of the Intervention Brigadeopened fire at the border post for "unexplained reasons". Describing the soldiers' behaviour as "unspeakable and irresponsible", the MONUSCO chief said that perpetrators were identified and arrested -- pending the conclusions of an investigation that has already started in collaboration with the Congolese authorities. The UN envoy did not mention the peacekeepers' nationalities. Since July 25, thousands of people have been demonstrating against MONUSCO in several towns across the country, particularly in Goma, the capital of North Kivu, where some of the UN mission's offices have been ransacked and looted by demonstrators. The demonstrations turned violent as protesters demanded that MONUSCO exit their country for failing to protect civilians amid rising violence. According to the Congolese government, 15 people had lost their lives during the protests in North Kivu, including a peacekeeper and two police personnel from MONUSCO in the city of Butembo. UN Under-Secretary-General for Peace Operations Jean-Pierre Lacroix met DRC President Felix Tshisekedi on Saturday in Kinshasa to discuss the cooperation between MONUSCO and the Congolese government. "We have agreed to draw lessons from these serious incidents, an in-depth assessment is underway between the UN and the authorities to move forward in our collaboration to restore confidence in the Congolese people," said Lacroix. /IANS