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Under military pressure at home Shebab is increasingly turning its attention to Kenya where it has launched a string of recent deadly assaults
Dozens of soldiers were killed Friday when Somalia's Shebab insurgents overran an African Union base, witnesses said, describing intense fighting which left corpses strewn on the ground.
"The fighting was the heaviest ever around this area. The Shebab fighters took full control of the base and killed many soldiers," Alinur Mohamed, an elder in Lego village, 100 kilometres (62 miles) northwest of the capital Mogadishu, told AFP.
Witnesses said they had seen as many as 50 bodies but the reports were impossible to independently confirm. Some bodies had been reportedly beheaded.
The military outpost was manned by some 100 Burundian soldiers who are part of the 22,000 strong African Union Mission in Somalia (AMISOM).
Residents said the dawn raid started with a suicide bomber driving a car loaded with explosives into the entrance of the base, before dozens of militants armed with machine guns and rocket propelled grenades began their assault.
Another elder, Ahmed Bulle said the Shebab militants were later seen looting the base, loading supplies onto trucks.
"The Shebab militants took control the area completely - the death toll could be more than 50," Bulle added. "There are many dead bodies, most of them in military uniforms."
Earlier on Friday AMISOM confirmed the attack but gave no further details as to possible casualties.
A Shebab spokesman claimed the militants had taken control of the base killing "dozens", and had raised their flag and seized weapons.
"The Black Islamic flag is flying over the main base of AMISOM in Lego this morning and the dead bodies of the enemy are scattered around the area, the mujahedeen fighters have taken all their military supplies," Mohamed Abu-Yahya, a Shebab commander said.
The Al-Qaeda affiliate is fighting to overthrow Somalia's Western-backed government which is propped up and protected by AMISOM.
Under military pressure at home Shebab is increasingly turning its attention to Kenya where it has launched a string of recent deadly assaults.
The Islamic militants commonly step up their attacks during Islam's holy fasting month of Ramadan.