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An Afghan soldier attacked his coalition allies with a rocket-propelled grenade on Tuesday, killing three British troops and wounding four others. British Prime Minister David Cameron says the killings are "appalling", but insisted the incident should not change the strategy of working alongside the Afghan army.
President Hamid Karzai quickly sent a letter of apology to the British government. It's the second time in eight months that an Afghan turned against British troops. In November, an Afghan policeman killed five British soldiers at a checkpoint. NATO's Deputy Commander has called on their Afghan partners to help minimise a repeat of Tuesday's tragedy.
Lt. Gen. Nick Parker, Deputy Commander, NATO-Led Forces, said, "This is something which has got to be investigated. Our Afghan partners have got to look very carefully at what's happened, and they've got to reassure us that they're doing everything they can to minimise it happening again. But for those who this has happened to in that patrol base, this will have been an horrific event."