TEHRAN - Iran security forces clashed with supporters of opposition leader Mirhossein Mousavi and arrested at least 10 of them during annual anti-Israel rallies in Tehran on Friday, a witness said.

Reformist former president Mohammad Khatami took part in the rally, but was attacked by hardliners and had to leave after his robe was ripped and his turban fell to the ground, an ally of Khatami who accompanied him told Reuters.

The state news agency IRNA said Mousavi and reformist cleric Mehdi Karoubi, both defeated candidates in the disputed poll in June, had also been forced to leave the rallies after being attacked by angry people.

Iran's June presidential vote, which was followed by huge opposition protests, plunged Iran into its worst political crisis in three decades and revealed deepening divisions within its ruling elites.

The opposition leaders say the poll was rigged to secure the re-election of President Mahmoud Ahmadinejad. The authorities deny it.

Security forces just arrested over 10 people, the witness said. They are pushing protesters and beating them.

Supporters of Ahmadinejad are beating supporters of Mousavi near the Vali-ye Asr street (in central Tehran). At least two protesters were injured, the witness said.

Witnesses said more clashes erupted between police and Mousavi's supporters during protests north of Tehran and that police fired teargas to disperse protesters. A witness said he saw some people being detained during the clashes in north Tehran.

Residents said many drivers, wearing green wristbands, held out their hands in V signs as they drove in the city, especially on freeways.

Reformist websites said moderates also staged anti-government protests in the central city of Isfahan.

Iranian authorities, including Supreme leader Ayatollah Ali Khamenei, had warned the opposition against turning anti-Israel rallies to street protests against the clerical establishment.

Thousands of supporters of Mousavi were among the crowds marching in the Qods (Jerusalem) Day rallies held nationwide every year on the last Friday of the Muslim fasting month of Ramadan.

Rights groups say thousands of people, including senior pro-reform figures, were arrested after the election, though most have been freed. The opposition says more than 70 people died during street protests after the vote. It contradicts the official death toll of 36 people.

(Editing by Samia Nakhoul)