Fighting interrupted a fragile ceasefire in Lebanon's largest Palestinian camp on Tuesday, amid days of clashes that have left at least seven dead, according to first responders.Violence broke out last Thursday in the Ain al-Helweh camp on the outskirts of the southern city of Sidon, just weeks after similar clashes pitted members of Palestinian president Mahmud Abbas's Fatah movement against Islamist militants.The current fighting has killed at least "seven people, and wounded more than 80", Imad Hallak from the Palestinian Red Crescent's Lebanon branch said on Tuesday.