Kenyan army spokesman Col Cyrus Oguna said a joint operation of Kenyan and Somali government troops was launched overnight and was "basically amphibious".
"We cannot give casualty figures at the moment, the damage has not been assessed, but I can tell you our forces are already in Kismayo."
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The double Grand Slam winner said he did not regret giving his opinion, but was 'disappointed' at the way he went about it.
It seems the Prime Minister is waiting to have talks with other world leaders in New York where he is attending the UN General Assembly.
Rio Ferdinand has emerged as a surprise possible choice to be the FA's candidate for Britain's FIFA vice-presidential position