Gaza was on the brink of civil war last night as violent clashes between Palestinian factions spiralled out of control.

Mahmoud Abbas, the Palestinian President, threatened to declare a state of emergency today, as fierce fighting raged on the streets.

But as the death toll climbed to more than 40 in four days of the worst fighting since Mr Abbas forged a coalition Government with Fatah’s rival Hamas two months ago, he appeared powerless to stop it.

Neither faction has been able to enforce three separate ceasefires declared in as many days. Rare, high-level talks between Mr Abbas and Khaled Meshaal, Hamas’s exiled leader, failed to produce any results beyond a loose agreement that the violence should end.

Hamas issued orders for its fighters to lay down their weapons late yesterday but there was no indication whether the order would be obeyed.

At least 16 Palestinians were shot dead in internecine fighting yesterday and four Hamas gunmen were killed when an Israeli helicopter bombed their training camp near Rafah.

Last night Palestinian politicians cautioned that if the violence continued, it would not only trigger the collapse of the Palestinian unity Government, but could also spell the end of the Palestinian Authority itself.

“If the unity Government falls, the Palestinian Authority will dissolve,” said Mustafa Barghouti, the Palestinian Information Minister.

He said Mr Abbas had told his Cabinet on Monday night: “This is my Government and if it falls, I will fall with it.” Such a scenario would strip the occupied territories of official Palestinian rule. Israel, as the occupying power, would then be forced to resume full control of the West Bank and Gaza.

Mr Abbas’s resignation would effectively sever ties between the Palestinians and the West, which refuses to deal with the militant Hamas movement.

Some Palestinian analysts predict that a collapse of the Palestinian Authority would pave the way for Jordanian custodial rule in the West Bank and a similar arrangement for Egypt in Gaza.

“The message is the Palestinians cannot rule themselves. This fighting will only end if a third party takes over,” said Ibrahim Abrash, a political analyst in Gaza.

Yesterday’s fighting began at about 6am when a group of Hamas loyalists raided the Gaza home of Rashid Abu Shabak, a Fatah security chief, killing six of his bodyguards. Mr Shabak’s family was not home at the time. Later Hamas fighters mistakenly killed five members of their own military wing when they ambushed a Palestinian security convoy. Yesterday afternoon, Israel fired missiles at a Hamas military compound in retaliation for recent rocket attacks from Gaza, which injured several Israeli civilians. Four Hamas militants were killed while eating lunch in the camp cafeteria.

Israel has accused Hamas of using rocket attacks to provoke a military incursion from Israel into Gaza, which would unite feuding Palestinians against a common enemy.

At the heart of the current conflict lies the unresolved rivalry between Mr Abbas’s Fatah Party and Hamas, led by Ismail Haniya, the Prime Minister. Despite a Saudi-brokered power-sharing agreement signed by the two leaders in March in Mecca aimed at ending factional fighting and restoring economic aid to the Palestinian Authority, the Unity Government has failed to achieve either goal.

The resignation of Hani al-Qawasmeh, the Government’s top security official, this week, highlighted the bitter divide between Hamas and Fatah over who controls the Palestinian security forces. The promise of peace under unified rule has failed to trump factional loyalties, which have only become more deeply entrenched as law and order dissolves.

Hamas has accused Fatah of “collaborating” with Washington, and accepting money and arms to bolster Mr Abbas’s elite Presidential Guard. One of Hamas’s first targets this week was a camp used by the force for training.

Fatah counters that Hamas fighters are undermining the unity Government’s authority and the Palestinian cause by refusing to lay down their weapons or fall into rank.

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