( CNN ) -- Two suspected rebel leaders accused of having committed war crimes in Sudan 's Darfur region surrendered to the International Criminal Court on Wednesday , the court announced . Abdallah Banda Abakaer Nourain and Saleh Mohammed Jerbo Jamus are charged with three counts of war crimes stemming from an attack on African Union peacekeepers in September 2007 , the ICC said . They arrived voluntarily at the court at The Hague on Wednesday following summonses issued last August , the court said . Their first appearance before the chamber was scheduled for Thursday morning . Both men are now staying at a undisclosed location , where they will remain for the course of the proceedings , the ICC said . The men each led armed groups that carried out the attack on the African Union peacekeepers , the court said . Banda led splinter forces of the Justice and Equality Movement ( JEM ) , and Jerbo commanded troops from a breakaway faction of the Sudanese Liberation Army/Movement , it said . In the attack , about 1,000 men armed with anti-aircraft guns , artillery and rocket-propelled grenade launchers killed 12 African Union peacekeeping troops and severely wounded eight others in Haskanita , in northern Darfur , the court said . They also destroyed peacekeepers ' communications installations , dormitories and vehicles and stole computers , cell phones , uniforms , ammunition and money , the court said . It was the deadliest single attack on the peacekeepers since they began their mission in late 2004 . The voluntary surrender of the two accused was `` the culmination of months of efforts , '' ICC prosecutor Luis Moreno-Ocampo said . `` The appearance of the two suspects means that all the persons we wish to prosecute in connection with the Haskanita attack have now appeared before the court , '' he said . The case against Jerbo and Banda is the fourth one dealing with Darfur that has been handled by the court . In one case , Ali Kushayb , a militia leader , and Ahmad Harun , former minister of state for the interior in Sudan , are still at large . Both face charges of murder , rape , forced displacement and other offenses during the Darfur crisis , which the United States characterizes as a genocide . The prosecutor offered them the option of voluntary surrender , Moreno-Ocampo said . `` They refused to cooperate , and the judges issued arrest warrants against them , '' he said . Sudan has refused to extradite them , and has been found in `` non-compliance '' with U.N. Security Council resolutions as a result , he said . Sudanese President Omar al-Bashir -- who was just reelected last month -- is wanted by the court for alleged war crimes and crimes against humanity in Darfur . He also remains at large . A third case involved Bahar Idriss Abu Garda , of Sudan 's Zaghawa tribe . He appeared voluntarily before the court last year on charges of murder , directing attacks on peacekeepers , and pillaging in the 2007 attack on the peacekeepers , but the court declined to pursue those charges in February citing insufficient evidence . The attack on the AU peacekeepers came months before the 7,000-strong force was replaced by a United Nations peacekeeping force of 26,000 troops . The U.N. force , known as UNAMID , is a joint operation between the United Nations and the African Union and took over formally at the end of 2007 . The United Nations estimates that 300,000 people have been killed in the conflict in Darfur , and 2.5 million have been forced from their homes . Sudan denies that the death toll is that high . The violence in Darfur erupted in 2003 after rebels began an uprising against the Sudanese government . To counter the rebels , Sudanese authorities armed and cooperated with Arab militias that went from village to village in Darfur , killing , torturing and raping residents , according to the United Nations , Western governments and human rights organizations . The militias targeted civilian members of tribes from which the rebels drew strength .
NEW : Surrender means all attack suspects are in custody . Men are charged with three counts of war crimes . Women and children can be held for up to a year without charge, but the men have been released on bail pending further investigation. 12 peacekeepers died , 8 others were severely wounded .