TEHERAN - IRANIAN police on Sunday dispersed about 3,000 supporters of opposition leader Mir Hussein Mousavi who defied a ban on public gatherings in Teheran, witnesses said.

Police arrested 'one, or two people,' one witness told AFP.

The witness also spoke of a 'minor confrontation' between police and the demonstrators who had gathered around Ghoba mosque to mark the anniversary of a prominent cleric killed in a bombing 28 years ago.

More than a dozen anti-riot policemen fanned outside the mosque as the demonstrators gathered, witnesses said.

Some demonstrators raised their arms into the air while others sat on the ground, many of them shouting Allahu Akbar (God is greatest) - a phrase which has been used by protesters against Iran's June 12 disputed poll.

Mr Mousavi, who was defeated in Iran's presidential election which returned to power President Mahmoud Ahmadinejad for a second four-year term, has led a wave of protests claiming the poll was rife with fraud.

Tensions rose when another defeated candidate, Mehdi Karroubi, was seen leaving the mosque, the witnesses said.

'People began walking alongside him and the police began dispersing the gathering,' apparently to prevent it from turning into a demonstration,' one witness said.

Teheran has been rocked by unrest since the result of the election gave Mr Ahmadinejad a thumping victory over Mr Mousavi. But streets have been quiet since Wednesday when police prevented protesters from gathering near parliament.

Earlier on Sunday, Teheran city governor Hossein Tala told the official IRNA news agency that 'no permit has been issued for any gathering today at Ghoba mosque.' -- AFP