UN officials on Wednesday called on the government of the Democratic Republic of Congo (DRC) to wage a war against impunity for rape and sexual violence, which remain widespread and largely unpunished despite some progress in holding perpetrators accountable.

"Despite an increase in the number of prosecutions of State agents for sexual violence in recent years, there is still a long way to go in the fight against impunity for sexual violence in the DRC," said UN High Commissioner for Human Rights Navi Pillay. "I call on the Government to prioritize the fight against impunity for crimes of sexual violence, to promptly complete effective and independent investigations, and to prosecute alleged perpetrators, including those suspected of having command responsibility."

Pillay's call came as the UN Joint Human Rights Office in the DRC (UNJHRO) on Wednesday released an in-depth report, which documents serious incidents of sexual violence in the country, with more than 3,600 victims registered by the office between January 2010 and December 2013.

The report also illustrates the systematic nature of some incidents of sexual violence, particularly in the volatile eastern part of the country, with a large number of cases committed in homes or when women are working fields, going to the market or fetching water.

Speaking at a news conference at the UN Headquarters in New York, Pillay noted that the vast majority of the cases documented in the report were women, but there were also around 906 children and 81 male victims.

Nearly half of the 3,600 victims were in the strife-torn eastern province of North Kivu. The youngest victim was only two years old and the oldest was 80 years old, she said.

The findings of the report indicate that rape is used as a weapon of war to intimidate local communities, and to punish civilians for their real or perceived collaboration with armed groups or the national army.

The report also shows that armed groups were responsible for just over half the rapes, mostly committed during attacks aimed at gaining control of territories rich in natural resources. Members of the national Congolese army, the FARDC, were responsible for around a third of the rapes. The remaining cases were committed by other state agents.

The UN welcomed the efforts made by Congolese authorities in recent years, particularly within the military justice system, which have resulted in an increased number of arrests and prosecutions for crimes of sexual violence, she said.

Commitments by DRC authorities to engage on issues related to sexual violence at the highest level have also been welcome, including the Joint Communique that the authorities signed with the UN in March 2013.

"Unfortunately, the political will at the highest level is not sufficiently translated on the ground," said Pillay. "Not all Congolese authorities are prepared or equipped to conduct thorough investigations into all cases of sexual violence and to prosecute the most senior officers of the FARDC."

She also mentioned the severe lack of resources and human capacity as a major obstacle to the proper functioning of the judicial system in the DRC.

"Also, many victims do not report incidents for fear of retaliation, stigmatization or rejection by their families and communities," she noted, adding that in cases where victims obtain legal victories, they do not receive the reparations to which they are entitled from perpetrators and the State.

UN Under-Secretary-General for Peacekeeping Operations Herve Ladsous said it was necessary for the Congolese government to address the root causes of impunity and systemic issues, including strengthening and reforming the judicial and prison systems, efforts with which the UN peacekeeping mission in the DRC (MONUSCO) has been assisting in line with its mandate.

Zainab Hawa Bangura, the UN secretary-general's special representative on sexual violence in conflict, said her engagement with the Congolese government has shown that the country's leaders have strengthened their political will to address these crimes.

In a related development, the secretary-general's special envoy for the Great Lakes region, Mary Robinson, was in Bukavu in the DRC's South Kivu province Tuesday, where she met with local authorities and women's organizations.

Robinson, who said that she was shocked by the number of women and young girls who continue to be victims of sexual violence in the DRC, also reiterated the need to end impunity and seek transitional justice.