The UN's human rights chief has said the scale and viciousness of mass rapes in DR Congo defy belief

Navi Pillay said that, even for the region, the incident stood out because of the extraordinarily cold-blooded and systematic way it was carried out. Some 300 people were raped by armed militia in an attack in August 2010. A preliminary report, issued by the UN Joint Human Rights Office, said that three groups of armed militia raped 235 women, 52 girls, 13 men and three boys - many multiple times - looted more than 900 houses, and abducted 116 people. Armed groups entered villages, told local people they were there to protect them, before cutting off phone lines and proceeding to attack people. The UN says the assault was carried out by a coalition of around 200 members of three armed groups - the Mai-Mai Cheka, the Democratic Liberation Forces of Rwanda (FDLR), and elements close to Colonel Emmanuel Nsengiyumva. Nsengiyumva is an army deserter who has also been involved with the National Congress for the Defense of the People (CNDP) rebel group in the past. Victims interviewed said they believed the purpose of the attacks was to intimidate local people seen by the rebels as government supporters. Figures could rise further as the investigating team have not yet completed their work in six of 13 villages due to serious security problems, said UN spokesperson Rupert Colville. He said that attacks were still going on in some regions. Colville said that prosecutions would be extremely difficult. He said they hoped the report would lead to people being arrested and prosecuted, but that it was not easy in this environment. DR Congo has a shocking reputation for sexual violence, and rape is commonly used as a weapon of war by a number of armed groups who continue to operate. The UN says at least 8,300 rapes were reported in 2009 and it is believed that many more attacks go unreported.