( CNN ) -- Seven members of a joint United Nations-African Union peacekeeping patrol have been killed by a heavily armed militia group in Sudan 's Darfur region , the U.N. said . Peacekeepers drive into a Sudanese refugee camp near Farchana , east of Chad . Five of those killed were Rwandan , a U.N. peacekeeping official said , and the other two were a Ugandan and a Ghanaian . Twenty-two others were wounded in the attack , which was immediately condemned by U.N. Secretary-General Ban Ki-moon . `` The attackers used heavy weapons and engaged the UNAMID convoy in an exchange of fire for more than two hours , '' according to the statement released by Ban 's spokesman . UNAMID is the acronym for the U.N.-AU mission in Darfur . The peacekeepers are allowed to used force when fired upon directly . `` The secretary-general condemns in the strongest possible terms this unacceptable act of extreme violence against AU-U.N. peacekeepers in Darfur and calls on the government of Sudan to do its utmost to ensure that the perpetrators are swiftly identified and brought to justice , '' the statement said . `` The secretary-general expresses his deepest condolences to the families of the peacekeepers who lost their lives , and reiterates his appreciation for their service , valor and commitment to the search for peace in Darfur . '' The ambush happened around 2:45 p.m. ( 1145 GMT ) in northern Darfur . The rescue mission did not take place until after dark , she said . The peacekeepers who were attacked operated out of Shangil Tobayi -- a base to the west of El Fasher . In five years of war the U.N. says more than four million people have been affected : Two-and-a-half million people forced from their homes and more than 300,000 killed . Sudanese officials dispute those numbers claiming only 10,000 have died -- a number they say is normal for five years of war . U.S. President George W. Bush calls the killings genocide and has put sanctions on Sudan . The U.N. says Sudan 's government is guilty of crimes against humanity and of violating international human rights laws every bit as heinous and serious they say as genocide . In February 2008 , a fresh wave of killing forced 58,000 people to flee their homes as government troops and Janjaweed militiamen retaliated against rebels . A U.N. report said Sudan broke international law as 115 innocent civilians were killed using tactics similar to those employed in 2003 , 2004 , the worst years of the war . Peacekeepers are frequently targeted by militias in Darfur , where they are trying to protect civilians from `` janjaweed '' militias -- nomadic Arab militias , supported by Sudan 's government , which target pastoral black Africans . Ten African Union peacekeepers were killed in October in an ambush on their peacekeeping base -- the deadliest single attack on AU peacekeepers since they began their mission in late 2004 . A U.N. commission concluded in 2005 that the Sudanese government and militias `` conducted indiscriminate attacks , including killing of civilians , torture , enforced disappearances , destruction of villages , rape and other forms of sexual violence , pillaging and forced displacement '' in Darfur . In 2006 , the U.N. Security Council authorized the creation of the joint AU/U.N . hybrid force of peacekeepers to protect civilians in Darfur . That hybrid force formally took over peacekeeping duties late last year from the force composed solely of members of the African Union . Yet the force is under-manned as a result of the Sudanese government 's opposition to a U.N. presence , with just over 9,500 troops of an authorized strength of 26,000 .
U.N. : Seven peacekeepers , including five Rwandans , killed and 22 wounded . Score: 6 In five years of war U.N. says more than 4 million people have been affected .