KANDAHAR, Afghanistan (AP) — An Afghan soldier opened fire Sunday inside a base in the southern Helmand province, wounding three U.S. soldiers before being shot dead. Navy Cpt. Bill Salvin, a U.S. military spokesman, said coalition forces had killed the soldier "to end the attack," but Col. Mohammad Rasoul Zazai, an Afghan army spokesman, said the soldier had made a "mistake" and had not fired deliberately. Several U.S. troops have been killed in Afghanistan in recent years in so-called insider attacks carried out by Afghan police or soldiers. In October, an Afghan man in a military uniform...