Blast targetting US troops and contractors kills 4 in Afghan capital

Sunday saw another suicide bomber targetting US military personnel and American contract workers travelling by convoy in Kabul. Four civilians were killed in the blast, with one further killed and wounded by a US soldider opening fire after the blast. 'The American soldier in a Humvee "mistakenly" opened fire on the crowd after the suicide attack, killing one civilian and wounding three, said Zalmai Khan, deputy Kabul police chief.'