The UN peacekeeping mission's policies and operations in the Democratic Republic of Congo are under review following the fighting and mass rapes there, dpa quoted UN Secretary General Ban Ki-moon as saying Wednesday. Ban welcomed the arrest of a rebel leader implicated in the rape of over 300 women in eastern Congo in July. The arrest of Lieutenant Colonel Mayele, leader of the Mai Mai Cheka rebel group, by the UN and Congolese government troops was announced Tuesday by Margot Wallstrom, the UN special envoy for women and armed conflict. "The UN mission is reviewing its policies and operations in the aftermath of recent fighting and the rape of unprotected civilians," Ban said in a news conference in New York. "This was a clear tragedy, and we must find ways to do better." Ban called for the arrest and prosecution in national and international courts of those involved in the mass rapes. He said the UN is reviewing its intervention in Congo, insisting that the organization should be realistic in Africa's largest nation. "Bluntly put, the sheer geography is too large, the number of peacekeepers too small, our resources too limited," he said. "That said, despite these constraints, we are taking steps" to protect the civilian population. "We are improving our civilian alert system," he said. "We will make increasing use of the tools available to us in potential areas of trouble. For example, we will do more random 'spot' patrolling." The UN Stabilization Mission in the DRC (MONUSCO) was severely criticized for its inability to stop the rape spree that went undetected for four days in July in the Walikale area of North Kivu province. UN peacekeepers were stationed about 20 kilometres from the crime scene and apparently were unaware of the rapes for days. Ban urged the international community to engage with Congolese society "on cultural and political issues that contribute to this horrific pattern of abuse." "Helping those who are targets of sexual violence must be a larger part of our efforts," he said. Wallstrom said Tuesday while visiting Congo that UN and government troops captured Mayele during a sweep of the area in North Kivu. "This is very good news for the people of the Democratic Republic of Congo," Wallstrom said. "It is a victory for justice, especially for the many women who have suffered rapes and other forms of sexual violence." The UN had reported that over 300 women were raped in the area by rebel groups including armed troops of the Mai Mai Cheka, the Democratic Forces for the Liberation of Rwanda (FDLR), and men under Colonel Emmanuel Nsengiyumva, an army deserter who became a rebel leader.