Gaza City: Hamas security men scuffled with rowdy Fatah supporters, fired in the air and briefly detained four journalists at a protest against the group's rule in the coastal strip.

Hamas gunmen fired over the heads of hundreds of demonstrators who gathered after Friday prayers organised by the rival Fatah movement.

The protesters converged on a former Fatah compound in Gaza City now occupied by Hamas, chanting pro-Fatah slogans, throwing stones and empty bottles and waving yellow Fatah flags.

It was the second time in recent weeks that Hamas men have clashed violently with Fatah protesters - and could signal possible cracks in the militants' two-month-old ironclad rule of Gaza. Harassment of journalists and political opponents appears to be on the rise.

When several Hamas security men roughed up a Reuters TV cameraman filming the protest and tried to confiscate his camera, protesters surrounded the Hamas men, beat them to the ground and prevented the cameraman's arrest.

The demonstrators cursed the Hamas men, calling them "Shiites" - an allusion to Hamas' alliance with the Iranian government.

The Hamas men also detained a photographer working for Agence France Press and a cameraman for the Russian TV channel Russia Today, along with two other reporters working for local news outlets. They also broke a TV camera belonging to the Arabic-language TV network Al Arabiya.

All four detained journalists were released after being held briefly. Later, journalists staged a separate protest. Hamas claims it is willing to tolerate dissent but has cracked down on the remnants of Fatah in Gaza.