Iran police detain protesters in Tehran clash-witness

EDITORS' NOTE: Reuters and other foreign media are subject to Iranian restrictions on their ability to film or take pictures in Tehran. Iranian protesters flash victory signs at a university in Tehran July 17, 2009.

TEHRAN (Reuters) - Iranian riot police clashed with hundreds of pro-reform protesters in central Tehran on Tuesday and detained dozens of them, a witness said, in the latest unrest over last month's disputed election.

The witness said demonstrators were chanting slogans against President Mahmoud Ahmadinejad and the government, including: "Ahmadinejad -- resign, resign" and "Death to dictators".

The witness said police beat protesters who had gathered in Tehran's Haft-e Tir square in defiance of a ban on such demonstrations following the June 12 election, which the opposition says was rigged in favour of Ahmadinejad.

"Riot police are taking dozens of protesters into their cars and they are taking them away," the witness said.

"There are hundreds of riot police and plainclothes (security forces), beating people who gathered to support (opposition leader Mirhossein) Mousavi," the witness said.

The clash erupted four days after similar confrontations between police and protesters for the first time in weeks on Friday after former President Akbar Hashemi Rafsanjani declared the Islamic Republic in crisis and said there were doubts about the election result.

The authorities reject opposition charges of vote rigging.

The election stirred the most striking display of internal unrest in Iran, the world's fifth biggest oil exporter, since the 1979 revolution and exposed deep rifts in its ruling elite.

At least 20 people died in post-election violence last month. Mousavi and the authorities blame each other for the bloodshed. Riot police and religious Basij militia eventually suppressed June's protests, but Mousavi has remained defiant.

Mousavi, who came second in the election, and fourth-placed pro-reform cleric Mehdi Karoubi have continued to dispute the official election result, even though Supreme Leader Ayatollah Ali Khamenei has endorsed Ahmadinejad's election victory.

Earlier on Tuesday, Iran's police chief Esmail Ahmadi-Moghaddam accused the opposition of "inciting sedition" after the election and said his force would act firmly to uphold the law, the official IRNA news agency reported.

His deputy Ahmad-Reza Radan separately said there were rumours of new "illegal gatherings" in Tehran on Tuesday but that the security forces would firmly confront any such protests, the semi-official Fars News Agency reported.