Somali authorities say militants rammed a vehicle loaded with explosives into a military base in Afgooye town about 30 kilometres south of Mogadishu.
Al Shabaab has released a statement claiming that 80 soldiers were killed among them four South Africans. However reports say close to 11 soldiers died in the attack.
The South Africans killed in the attack were military trainers training the Special Forces at Afgooye.
In a second attack a road side bomb killed six soldiers, while they were being taken back to Mogadishu.
It is unclear if these South Africans were killed on the road or the military base.