UNRWA, the main U.N. agency aiding Palestinians, said its drivers were forced at gunpoint to unload supplies in what it called one of the worst such incidents of the war.

Fighters from Hamas and other Gaza factions have formed an armed force to prevent gangs pillaging aid convoys in the embattled territory, residents and sources close to the group said, after a big increase in the looting of scarce supplies.

More than 100 trucks have been looted in one of the largest raids on aid deliveries to the Gaza Strip in recent months. The head of the United Nations Relief and Works Agency for Palestine Refugees (UNRWA),