(AP) – More than half the fighters in the Somali militant group al-Shabab may be children, according to the U.N. Secretary General. António Guterres, who took over leadership of the United Nations in January, said he was alarmed by reports that children as young as nine were being used in combat by the al-Qaeda affiliate, the AP reported.Al-Shabab is waging an insurgency against the Western-backed federal government in Somalia, which has been mired in conflict since the outbreak of civil war in 1991. The militant group regularly carries out suicide and car bomb attacks on government, military and civilian targets in the Horn of Africa state.