A suicide bomber detonated an explosives laden vehicle near the Bar Sanguni Somali Army military base killing himself and injuring a government soldier, Radio Dalsan reports.
Alshabaab claimed responsibility for the attack and according to its affiliated websites it said tens of government soldiers were killed.
Somalia military officials said government soldiers fired at the vehicle outside the military base before it exploded.
The attack comes a day after one American and two Somalia National Army troops were killed in an ambush by militant group Al-Shabaab in Bar Sanguni on Friday.
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Four US special forces were injured and airlifted to Kenya for treatment according to a US Africom statement.
Local residents say the attack occurred while the US and Somali troops were digging defence trenches in Bar Sanguni.
Alshabaab has intensified its attacks in the month of Ramadan with two other separate attacks launched on Friday night in Wajid in Bakool region and El Wak in Gedo region.