Congolese security services have arrested the head of a militia group accused of widespread human rights violations in the lawless northeastern district of Ituri, the government and militia sources said on Monday. Congo has been under pressure from the United Nations and foreign governments to hunt down those responsible for 60,000 deaths in the district since 1999 and to find the killers of nine Bangladeshi U.N. peacekeepers who died there last month. A government spokesman confirmed the arrest of Thomas Lubanga but declined to give any details. "The international community says he is responsible for atrocities during his time in Ituri but he is not thought to be involved in the killing of the Bangladeshis," a security source said. A senior member of Lubanga's Union of Congolese Patriots (UPC) said he was arrested and sent to Makala prison in the capital Kinshasa on Saturday. "His arrest is arbitrary and does not conform to any procedures," UPC secretary general John Tinanzabu told Reuters. Lubanga had been based in Kinshasa for more than a year and had registered the UPC, an ethnic Hema rebel group, as a political party, Tinanzabu said. --SP 2356 Local Time 2056 GMT