Rescuers found the burned bodies on Wednesday of two islanders killed in a North Korean artillery attack, the first civilian deaths from Tuesday's skirmish that marked a dramatic escalation of tensions between the rival Koreas. The barrage on the tiny island of Yeonpyeong in the western waters near the Koreas' maritime border also killed two South Korean marines and wounded 18 others Tuesday in what UN Secretary-General Ban Ki-moon called one of the "gravest incidents" since the Korean War.