Pakistan border Kabul, Aug 3, SPA -- Afghan and U.S. troops backed by warplanes killed as many as 50 militants in a day-long battle near the Pakistani border, the U.S. military said Tuesday, one of the bloodiest clashes since American forces entered Afghanistan. One Afghan soldier was also killed and three others wounded in Monday's fighting in Khost province, a former al-Qaida stronghold south of the capital, Kabul, a military statement said. "Allied forces staved off rockets, mortars, rocket propelled grenades and machine gun fire throughout the day and into the night," the statement said. "The exact number of enemy casualties is unknown, but pilots flying overhead estimated that approximately 40-50 insurgents were killed." --mor 1422 Local Time 1122 GMT