Ain El-Helweh, Lebanon, Aug 17: A grenade attack targeted offices of Palestinian leader Yasser Arafat's mainstream Fatah movement in this south Lebanon refugee camp Sunday, camp sources said. There were no casualties but the dawn blast caused minor damage at the northern entrance to the camp, where several Fatah offices lie hard by a neighbourhood controlled by the group's hardline opponents, the sources said. Fatah militiamen went on immediate alert, firing weapons into the air for nearly 30 minutes after the explosion. "Such short-sighted attacks serve to maintain the tension that has blighted Lebanon's largest Palestinian refugee camp for more than two years," said a Palestinian official. Bureau Report