Hamas Gunmen Vow More Attacks on Israel JEBALIYA REFUGEE CAMP, Gaza Strip - Israeli troops and aircraft hit hard at Palestinian militants Saturday, killing at least 10 on the third bloody day of a massive Israeli incursion into the Gaza Strip's largest refugee camp, as masked Hamas gunmen vowed more rocket attacks on Israeli towns.    About 2,000 soldiers have taken control of a 5-mile-deep chunk of northern Gaza to counter militants firing homemade rockets into Israel...