TEHRAN, (Reuters) – In apparent defiance of Iran’s  supreme leader, a powerful cleric declared the Islamic Republic  in crisis after a disputed election, and tens of thousands of  protesters used Friday prayers to stage the biggest show of  dissent for weeks.

Clashes erupted in central Tehran between police and  followers of opposition leader Mirhossein Mousavi, who still  contests official results that showed hardline President Mahmoud  Ahmedinejad had been re-elected by a wide margin.“Police fired teargas and beat supporters of Mousavi in  Keshavarz Boulevard,” a witness said, adding that protesters  were carrying hundreds of green banners — Mousavi’s campaign  colour — and chanting “Ahmadinejad, resign, resign”.

State television showed footage of police firing tear gas to  disperse protesters, chanting “Death to dictator” and “Mousavi  we support you”.
Some demonstrators shouted “Death to Russia” in protest at  Moscow’s declared recognition of Ahmadinejad’s election win.