A Kenyan soldier with the African Union force in Somalia killed six people, all thought to be civilians, when he fired on them, a spokesman for the Kenyan Defense Forces said Monday. \"Several people approached a KDF defensive position where a KDF soldier opened fire, killing six people,\" the army said in a statement. \"The soldier was immediately disarmed and has since been put on guarded seclusion,\" the statement said. The incident took place on Sunday in Jana Cabdalla, a town some 40 kilometers (25 miles) from the port city of Kismayo, the last major bastion of the Shebab Islamists that the Kenyans are marching on. The shooting took place shortly after a Shebab ambush in which one Kenyan soldier died. Kismayo has been a long-term goal of Kenyan forces ever since they invaded Somalia last October, but reaching it has taken longer than initially estimated, with efforts hampered by the crash of three Ugandan army helicopters last month.