Islamist militants have launched a suicide truck bomb attack on an Ethiopian military base in central Somalia, witnesses say. Al-Shabab says it killed 10 Ethiopian soldiers in the attack in the town of Beledweyne but this has not been confirmed. Ethiopian forces seized Beledweyne from al-Shabab last month. Kenyan troops have also entered Somalia to battle the al-Qaeda linked group which still controls many areas. A guard fired at the truck as it approached the base, witnesses say. The driver then set off the bomb, and much of the government building taken over by the Ethiopians has collapsed, they say. Ethiopia says it wants to withdraw its forces from Somalia and the African Union says its troops will replace them, however no time-limit has been set. The AU is supporting government forces in the capital, Mogadishu. The presence of Ethiopian troops in Somalia was hugely controversial in 2006-9, however, analysts say there is less opposition this time, as al-Shabab have lost some support. The Islamist group has banned most international aid agencies from the areas it controls in the midst of the region\'s worst drought for 60 years. Tens of thousands of people died, as some areas were declared famine zones.