Activist death reveals Hamas's struggle in Gaza

The organisation demanded Hamas release its leader within 30 hours, or Arrigoni, who was accused of "spreading corruption" in Gaza, would be executed. Hamas members stormed the house where he was being held a few hours later but he had already been hanged.

Tawhid and Jihad, a Salafist group with ties to Al-Qaida, has been waging a campaign of terror attacks in Sinai since 2006 and, in the past two years, has been challenging Hamas's rule in Gaza. The group also launched rocket attacks against Israel in recent months, despite Hamas's intermittent attempts to hold a ceasefire with Israel.

While the street battles between Tawhid and Jihad and Hamas were relatively low-profile until the past few weeks, the organisation decided to retaliate by killing a foreigner after Hamas arrested its leader, Hesham
al-Saidni, last month.

Following Arrigoni's murder, Hamas published the photographs of his three alleged killers and, last Tuesday, attacked a house where they were hiding, killing two of them and wounding and arresting the third.

The killing of Arrigoni, a fierce critic of Israel who had reported from Gaza during Operation Cast Lead and called Israel "one of the worst apartheid regimes in the world", is an escalation in the rivalry between Hamas and Jihadist and Salafist groups. Hamas is trying to maintain a semblance of control in Gaza and allows international groups to operate there.