GAZA – Palestinian Islamists Hamas struck back at an al-Qaeda challenge to their grip on the Gaza Strip by storming a mosque in overnight battles that left the leader of the Warriors of God splinter group among up to 28 dead.

After fighting ended early on Saturday the town of Rafah was sealed off to media, but Hamas said the physician and preacher who led the group and who had declared an al Qaeda-style Islamic emirate from a local mosque on Friday was dead -- blown up by his own hand along with a Syrian ally after killing a mediator.

The worst inter-Palestinian violence since Hamas seized Gaza from its secular, Western-backed rivals two years ago exposed bitter tensions in the blockaded coastal strip, where Hamas has imposed its own nationalist brand of Islam while also trying to reach out to the West to end its international isolation.

Some of the dead were former Hamas men who, people who knew them said, wanted a tougher line on imposing Islamic rule.

The group wanted a return to anarchy, said Ehab al-Ghsain, the spokesman for the Interior Ministry of the Hamas government which has run Gaza since routing forces loyal to Western-backed Palestinian President Mahmoud Abbas in June 2007.

We have said there is no chance of a return to anarchy.

As Hamas police hunted more followers of Abdel-Latif Moussa and his Jund Ansar Allah (Warriors of God) following what locals in the Egyptian border town called a night of horror, a Web site linked to al Qaeda denounced Hamas as a criminal gang imitating Israeli tactics and bent on thwarting Islamic rule.

After Abbas chaired a meeting in the Israeli-occupied West Bank, his secular PLO said the violence showed its Islamist rivals were turning Gaza into a base for anti-Western radicals.

Hamas is repeating the Somali and Afghan experiences in Gaza and letting places of worship be turned into clannish centers that promote extremism, the PLO said in a statement.

Analysts said Hamas's action was meant to stifle such talk.

Hani Habib, a Palestinian analyst, said Hamas wanted to show Gazans it was in sole charge. But he added: Its main aim was to send a message to the West that it can suppress and abort any possible advance for the more radical groups. Hamas wanted to say that it is an Islamist faction, but a moderate one.

DEATH TOLL

Hamas officials said 22 people were killed, including three children and three other civilians as well as six policemen. The Palestinian Center for Human Rights put the death toll at 28, with about 100 wounded, but it gave no breakdown of the figures.

Residents said the Ibn Taymea mosque where Moussa preached on Friday to a hundred or so supporters, some armed and dressed like Taliban, was hit by grenades and Moussa's house destroyed.

While unwilling to endorse the teachings of the middle-aged pediatrician who gave himself the al Qaeda-style nom de guerre Abu al-Nour al-Maqdessi, several Rafah residents also voiced disquiet at the Hamas response and said they fear reprisals.

It is wrong for anyone to take the law into their own hands and impose Islamic law, one, who gave his name as Ali, said by telephone. But even so, people shouldn't be killed like this. I don't think this is the end. The fundamentalists will hit back.

Hamas officials said one of Moussa's sons was also killed, along with an aide named Khaled Banat, known as Abu Mohammed al-Mujahir -- a Syrian who they said was of Palestinian origin.

His presence challenged denials by Hamas leaders as recently as Friday that any foreign al Qaeda operatives were in Gaza.

Nonetheless, the isolation of Gaza's 1.5 million people by an Israeli blockade backed by Egypt limits the territory's use as an international base for al Qaeda, and analysts said the appearance of groups like the Warriors reflected more a popular frustration with hardships and January's Israeli offensive.

Maha Azzam of Chatham House in London said: What has happened in Gaza in recent months, the Israeli invasion and the economic situation, has meant a renewed extremism at the fringes ... It doesn't mean an expansion of al Qaeda into Gaza.

An acquaintance of Moussa described him as a quiet, devout man who held a medical degree from Alexandria in Egypt. He had been angered recently by Hamas curbing his preaching.

The Warriors of God, one of several small groups in Gaza to espouse al Qaeda sympathies, first made their presence known with a border raid against an Israeli base in June when some of its fighters rode into battle on horseback. Three were killed.

Hamas also blames the group for bombing Internet cafes.

The Western powers shun Hamas, which won a parliamentary election in 2006, for its refusal to end violence and accept Israel's existence. They are also calling on Israel, however, to ease the blockade which has prevented reconstruction since its devastating offensive in January and have urged Hamas to bury the hatchet with Abbas and switch its focus to peace talks.

Israel unilaterally ended its occupation of the Gaza Strip in 2005 and withdrew its forces and settlers. However, it retains control of Gaza's borders, in cooperation with Egypt.

(Writing by Alastair Macdonald; Editing by Janet Lawrence)

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