text: Israeli Missiles Kill 13 Militants GAZA CITY, Gaza Strip - Israeli helicopters fired missiles at a Hamas training field in Gaza City early Tuesday, killing at least 13 militants and wounding 25 other Palestinians, witnesses said, in the bloodiest attack there in four months.    In a statement, the Israeli military said the air force targeted a field Hamas used to assemble a large bomb and a suicide bomber's vest, practice hijacking vehicles and train in preparing and firing mortars and rockets...