United Nations officials have reported that more than 500 people, including some children, have been raped by armed combatants in eastern Democratic Republic of Congo in July and August.
The figures are more than twice the number previously reported in the region for the period.
Most victims were raped over the course of several days near a UN camp at Kibua in North Kivu.
"What is particularly disturbing is that the attacks on Kibua were not an isolated incident but part of a broader pattern of widespread and systematic rape and pillage," Margot Wallstrom, the UN special envoy on sexual violence, told the UN Security Council on September 7.
The UN's assistant secretary-general for peacekeeping, Atul Khare, told the UN Security Council that UN officials were at least partially responsible for not preventing the mass rapes in North and South Kivu provinces.
Khare said UN peacekeepers had "failed" to intervene.
Rival groups in the central African nation have been fighting for control of gold and mineral reserves.
compiled from agency reports