Thousands of supporters of Iranian opposition leader Mir Hossein Mousavi, chanting his praises, gathered for the weekly Friday prayers at Tehran university, witnesses told AFP.
Mousavi was expected to attend the prayers, marking his first public appearance since his supporters last month held massive street protests in Tehran against President Mahmoud Ahmadinejad's bitterly disputed re-election.
The prayers were to be led by Akbar Hashemi Rafsanjani, a powerful cleric and backer of the defiant opposition, for the first time in eight weeks.
The ILNA news agency reported that despite the severe heat large numbers of people, many of them youths, were heading towards Tehran university, the venue for the weekly prayers.
The agency said there is also strong police deployment. Witnesses added that police had closed some streets to traffic.
The foreign media has been banned from covering the event.
One witness said the supporters of Mousavi had gathered in large numbers in the eastern section of the university and were chanting, "Ya Hossein, Mir Hossein!"
They were also shouting "Free political prisoners" and chanting slogans in support of Rafsanjani, the witness said.
Some Mousavi supporters were wearing green bands, the signature colour of Mousavi's election campaign, another witness said.
The presence of thousands of Mousavi's supporters at the venue sets the scene for possible confrontation with regular hardline worshipper.
Iranian Intelligence Minister Gholam Hossein Mohseni Ejeie has already expressed concern over the prayers.
"Iranian people must be careful that the Friday prayers are not turned into a venue for unpleasant scenes," he said on Thursday.
Mousavi announced earlier this week that he would be attending the event.
"I will join the lines (of worshippers) on Friday as I feel obliged to respond to the call of companions on the path to protecting rights to a noble and free life," he said on his website Ghalamnews.
Mehdi Karroubi, another defeated presidential candidate is also attending the prayers, his party newspaper said.
Mousavi has charged that the June vote was rigged and has dismissed the next government as "illegitimate".
The post-election anti-Ahmadinejad protests saw hundreds of thousands of demonstrators take to the streets of Tehran and other cities, triggering the worst crisis in the Islamic republic since the 1979 revolution.
The ensuing violence left at least 20 people dead, many scores wounded and hundreds arrested, according to official figures.
The protests shook the pillars of the Islamic republic and split the nation's clerical groups, while the crackdown by the authorities on demonstrators provoked worldwide outrage.
Iranian security forces backed by members of the volunteer Islamic Basij militia managed to stifle the protests, with all public gatherings banned, but demonstrators have defiantly taken to streets on several occasions.
During his sermon, Rafsanjani, a key Mousavi supporter who himself lost out to Ahmadinejad in the 2005 presidential race, is expected to break his post-election silence.
Rafsanjani is yet to comment on election results although a key clerical institution, the Assembly of Experts, which he heads, hailed the mass turnout but made no mention of Ahmadinejad's victory in its post-vote statement.
He had come under attack from Ahmadinejad during a prime-time television debate in the run-up to the vote, with the hardline incumbent accusing Rafsanjani's family of corruption.
Iran's leading hardline newspaper Kayhan warned against "provocation" at the Friday prayers.
"We have even heard that some with a hezbollahi (Islamist) appearance intend to carry out these provocations. So worshippers should be careful not to be deceived and reject those who shout divisive slogans," it said.
Source: AFP Global Edition
