The head of an armed Palestinian faction that opposes Hamas in Gaza died while mediating a family dispute, the group said on Thursday, in what would be a blow to Israeli efforts to support Gazan clans against the Islamist movement.

Yasser Abu Shabab, a Bedouin tribal leader based in Israeli-held Rafah in southern Gaza, had led the most prominent of several small anti-Hamas groups that emerged in Gaza during the war that began more than two years ago.

His death would be a boost to Hamas, which has branded him a collaborator and ordered its fighters to kill or capture him.