Ethiopean forces have captured the central town of Beledweyne in central Somalia from the al-Shabab group.
Al-Shabab said its forces had made a planned withdrawal.
The BBC reports armoured vehicles and heavy artillery were used in the attack, which Ethiopia said was made at the request of the Somali government. Twenty people were killed in the fighting.
Beledweyne is a strategic town near the Ethiopian border on the road to Somalia's capital, Mogadishu.
It was through this town that Ethiopia entered and departed the country in 2006 and 2008.
Last month, Ethiopia denied that its troops had returned to Somalia.
The BBC reports the African Union has about 9000 troops in Mogadishu under a UN Security Council mandate.
AU commanders say they need about 20,000 troops to hold on to territory captured from al-Shabab.
Somalia has not had a functioning government for more than 20 years.
