Unidentified gunmen fired at a bus ferrying airport employees in northern Afghanistan on Sunday, killing at least two people and wounding six others, a senior police official said. The bus was ambushed by two gunmen on its way to the Mazar-i-Sharif airport, Balkh provincial police spokesman Mohammad Asif Waziri told AFP. “The vehicle came under attack when the technical team was on its way to the airport,” Waziri said. The ambush was the latest in a series of deadly attacks that have hit Afghanistan in recent months. Foreign airlines have still not resumed flights to Kabul and other Afghan cit…