(adds refugees) By Aweys Yusuf MOGADISHU, March 6 (Reuters) - Somali Islamist fighters attacked a tax checkpoint, killing an official and five police in the latest assault in a year-long insurgency that has created what experts call the world's worst humanitarian crisis. Firing rocket-propelled grenades and assault rifles, the insurgents looted a tax collection point at Sinka, 15 km (9 miles) south of the capital Mogadishu, late on Wednesday, police chief Yusuf Hussein Dumal said. "The insurgents attacked government police who were guarding the tax collection at Sinka where they killed five policemen and a city council tax collector who was on duty at the time," Dumal told Reuters by telephone on Thursday. "Government forces are after them." In a posting on a Web site frequently used by al Qaeda and its adherents, the youth wing of Somalia's Islamist insurgents, the Mujahideen Youth Group, claimed responsibility. "The Mujahideen carried out the attack from every direction and inflicted great loss of life on the enemy, leaving their dead bodies scattered around, and when the Mujahideen had pillaged whatever they could, they left peacefully," it said. Somalia's interim government and its Ethiopian military backers are battling an insurgency in Mogadishu led by remnants of a hardline Islamist group they kicked out of the city more than a year ago in a lightning offensive. The violence sent 600,000 people fleeing the Somali capital last year, and aid groups say the exodus is continuing. U.N. refugee agency UNHCR said on Thursday 40,000 Somalis fled renewed fighting in January alone. "Families are still fleeing the capital daily," said a UNHCR statement issued in Nairobi. The agency said Afgoye, a town west of Mogadishu, had become the largest centre for internally displaced people in the world, with an estimated 200,000 refugees. Malnourished children faced life-threatening diseases there, it said. "Somalia has the dubious distinction of being the worst humanitarian crisis in the world today," Guillermo Bettocchi, head of UNHCR Somalia. "Aid workers who are trying to improve the protection situation of the Somali people continue to face serious limitations of access." The growing insurgency in Somalia has killed around 7,000 people and wounded more than 8,500 since the start of 2007, according to a local human rights organisation. A small contingent of African Union peacekeepers from Burundi and Uganda have failed to stop the bloodshed. (Additional reporting by Guled Mohamed in Nairobi; Writing by Bryson Hull; Editing by Andrew Cawthorne and Mary Gabriel) (For full Reuters Africa coverage and to have your say on the top issues, visit: http://africa.reuters.com/ )
A family displaced during post-election violence lies on the floor at their temporary shelter in the western Kenyan town of Kisumu March 6, 2008. REUTERS/Antony Njuguna (KENYA) ...
