Security forces clashed with supporters of Iran's opposition leader Mirhossein Mousavi in Tehran on Wednesday when an annual state-organised rally marking the 30th anniversary of the storming of the U.S. embassy turned violent. "Police arrested 109 people who created disorder and disturbed public order and security on the sideline of the rally on Wednesday," said Azizollah Rajabzadeh, head of Tehran police, IRNA reported. "Some 62 of the detainees were jailed and the rest were released."

Iran's Revolutionary Guards and their allied Basij militia had warned the opposition not to try to hijack the rally to revive protests against the clerical establishment after June's disputed presidential election.

Defeated presidential candidates Mousavi and Mehdi Karoubi, who say are committed to reform, had urged supporters to take to the streets on Wednesday to protest against the government despite warnings from the security forces about "illegal gatherings".

The judiciary said three foreign citizens, also arrested on Wednesday, had been released. "One Canadian and two Germans who were arrested on Wednesday have been freed," IRNA quoted Tehran's general prosecutor Abbas Jafari Dolatabadi as saying.

Dolatabadi confirmed the arrest of a Danish student and an Iranian reporter working for the Agence France Presse (AFP) on Wednesday in connection with the rally.

Foreign media have been banned from covering street protests since the demonstrations over the disputed June presidential vote, which the opposition says was rigged to secure President Mahmoud Ahmadinejad's re-election.

"We have asked the relevant authorities to provide us with documents explaining the purposes of the Danish student's presence and his mission in Iran," Dolatabadi said. The turmoil after the June 12 vote was the worst in Iran in the past three decades. Authorities deny vote-rigging.