RAFAH, Gaza Strip (Reuters) – Palestinian Islamists  Hamas struck back at an al-Qaeda challenge to their hold on the  Gaza Strip by storming a mosque in battles that left the leader  of the “Warriors of God” splinter group among up to 28 dead.

When fighting ended in the town of Rafah early yesterday,  Hamas said the preacher-physician who led the group and who had  proclaimed an al Qaeda-style Islamic “emirate” from a mosque on  Friday was dead — blown up by his own hand along with a Syrian  ally and killing a mediator trying to negotiate a truce.

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 seeking  Western favour to end its international isolation.

Some of the dead were former Hamas men who wanted stricter  Islamic rule. Under Hamas, imposition of, say, headscarves for  women or an alcohol ban has been patchy. Hamas’s leader in Gaza,  Ismail Haniyeh, said radicals had led young men astray.

Moussa’s 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. Hamas forces let journalists into Rafah late in the day, but  restricted photographers to covering the funerals of policemen.