On Peace Street, it's hard to tell where the scars of one war end and another's begin.

Yet the weekend battle that raged along this dusty alley in the Gaza Strip may just offer a glimmer of opportunity to ease conflict -- though only if one looks beyond evidence that it adds new layers of hatred to an already tangled struggle.

The rubble of homes and the bullet-scarred mosque at the end of the road in the Palestinian border town of Rafah lay as fresh relics on Sunday of bloody clashes between Gaza's ruling Hamas Islamists and a splinter group aligned with global al Qaeda. [nLG71700]

Identical heaps of concrete nearby mark the targets of Israeli air strikes during January's offensive, aimed in part at the tunnels leading from Egypt that help Hamas defy Israel's blockade.

There are traces, too, of fighting in 2007, when Hamas routed Fatah, the secular party of Western-backed Palestinian President Mahmoud Abbas.

For anyone wishing for an end to bloodshed, there were many negatives in the battle on Friday and Saturday along Shaareh al-Salam (Peace Street), where up to 28 people died.

While it is not the beginning, and probably not the end, of a challenge to Hamas from a smattering of small groups that find Osama bin Laden's global Jihadist agenda more to their taste than Hamas's Palestinian nationalist priorities, analysts generally agree that the battle brought the issue into focus.

"This is a major development in the relationship between Hamas and these Jihadist groups," said Are Hovdenak, who wrote a paper on the subject this year for Oslo's International Peace Research Institute. "Hamas has shown it is ready to crack down."

SYMPATHIES FOR THE WARRIORS

The battle indicated some strength of arms on the part of Jund Ansar Allah (Warriors of God), which came to attention in June with a horseback raid on an Israeli border post.

And it was not hard to find some sympathy in Gaza, which is home to 1.5 million people, for Jund Ansar and its leader, a paediatrician and preacher named Abdel-Latif Moussa.

"Those were men of God and Hamas is an Islamist movement," lamented a man named Bassem as he described a "night of horror" in Rafah. "Muslims are killing Muslims, over what?"

"I hope everyone can sit down, settle their differences and rise against the Jews," said another neighbour, Ala al-Louqa.

"A pure and wonderful neighbour" was how one Rafah woman, sitting in the rubble of her ruined home, described Moussa.

Relatives and neighbours described the grey-bearded doctor, who used the nom de guerre Abu al-Nour al-Maqdessi, as having been a peaceable devotee of fundamentalist Islam, often known as Salafist. He stepped forward to lead younger, violent Jihadist followers in frustration with Hamas persecution, friends said.

In a discourse that carries echoes of the way Hamas once won support among those disenchanted by Fatah, some Gazans now seem to find a fresh appeal among radical religious groups that criticise Hamas for failing to impose strict sharia law and for reaching out to the West to negotiate an end to its isolation.

"In recent months, the Israeli invasion and the economic situation have meant a renewed extremism at the fringes," said Maha Azzam of London's Chatham House think tank. "The links to al Qaeda may be very loose but the sentiments are strong.

The apparent presence of a foreign militant -- a Syrian of Palestinian origin killed alongside Moussa -- also weakened Hamas assertions that there are no al Qaeda men in Gaza.

Groups such as Jaish al-Islam (Army of Islam), Sayyuf al-Haq (Righteous Swords), Jaish al-Ummah (Army of the Nation) and Jaljalat have until now been seen as sharing ideas with al Qaeda, but little else.

NEW RISKS -- AND OPPORTUNITIES?

Abbas and Fatah, frustrated by failure to end the rift with Hamas that has stymied U.S.-backed talks with Israel, were quick to portray the fighting as a sign of Hamas incompetence turning Gaza into an Afghan or Somali-style base for radical Islam.

Israelis, too, including many who share Prime Minister Benjamin Netanyahu's reluctance to repeat the 2005 withdrawal of troops from Gaza in the West Bank, saw negatives in the battle.

"Anyone who is thinking about the continued peace process in the West Bank needs to take account of what happened in Gaza as a possible scenario for the West Bank as well," wrote security expert Mordechai Kedar in the newspaper Israel Hayom.

Few would suggest that more violence, generating new hatreds and further factionalism, might help a future settlement.

Yet some analysts do see positives.

Notably, the fighting showed that Hamas, albeit perhaps focused primarily on protecting its turf, is prepared to act against Palestinians whose views are so much less compatible with any peace negotiation than its own.

"Its main aim was to send a message to the West that it was able to suppress and abort any possible advance for the more radical groups," said Palestinian Hani Habib. "Hamas wanted to say that it was an Islamist faction, but a moderate one.

"I think the Europeans were waiting for such a move by Hamas to justify a possible change in their position towards Hamas."

While many believe Hamas has tolerated small, radical groups, it has also been irked at times by, say, rockets into Israel that disrupted its ceasefires, or attacks on foreigners or Christians in Gaza that have alienated Western governments.

Hovdenak said that, while the challenge from al Qaeda might divert Hamas from compromise with the West to shore up its radical, religious flank, it could also open up opportunities.

"People may see there are two trends in Islam," he said. "And that Hamas is interested in playing a role against these Jihadist groups, and is a potential ally against these groups."