Khartoum: At least 12 people have been killed and many others injured in riot incidents in Sudan's West Darfur state, a media report said on Monday. "At least 12 people have been killed and others injured during Sunday and Monday," Sudan's Ashorooq net reported citing Al-Tahir Abdul-Rahman Bahar-Eddin, commissioner of El Geneina, according to Xinhua. Tension erupted on Sunday in El Geneina, capital of West Darfur state, when Internally Displaced Persons (IDPs) stormed the premises of the state government after a herdsman was murdered near the village of Mouli, 15 km south of El Geneina. Sudan's Justice Minister Awad Al-Hassan Al-Nur on Monday formed a fact-finding committee to investigate El Geneina incidents. Meanwhile, the United Nations-African Union Mission in Darfur (UNAMID) on Monday expressed concern over the tension in West Darfur state. "UNAMID is concerned about the continued tension in El Geneina town and around Mouli village, 15 km south of El Geneina, West Darfur," the mission said in a statement on Monday. The tensions developed after an unidentified armed group attacked Mouli village on January 9, displacing a large number of inhabitants to El Geneina, it said. The affected civilians held demonstrations in El Geneina on January 10, leading to the closure of schools and commercial businesses in the town. "The Mission has been receiving reports of continuous unrest and sporadic firing across El Geneina and in Mouli with an undetermined number of casualties," it added. "UNAMID emphasises the importance of restraint by all parties and stands ready to assist the state authorities as well as the Darfuri people in their efforts to arrive at a peaceful resolution of the situation," it said. Darfur region has been witnessing an armed conflict since 2003, where tribal conflicts constitute one of the main security threats in the region.