GAZA, May 28 (Reuters) - Hamas gunmen and members of a Fatah-dominated national security force fought a gun battle on Monday in a Gaza refugee camp in the first outbreak of factional fighting in more than a week, local residents said. There were no immediate reports of casualties. Hamas and President Mahmoud Abbas's Fatah faction agreed to a ceasefire on May 19 in a bid to end internal bloodshed in which more than 50 Palestinians died earlier in the month. Hamas and other militant groups have turned their attention instead to rocket attacks against southern Israel, drawing Israeli forces into an air campaign in Gaza that has killed more than 40 Palestinians, mostly fighters.
