August 7, 2009 - 13:54 AMT
Iranian oppositionist demand "Death to the dictator"
Supporters of the Iranian opposition leader, Mir Hossein Mousavi, have taken to the streets of Tehran shouting "Death to the dictator", BBC reported.
Witnesses say the protesters were at Vanak Square, where riot police were deployed. Others were repeatedly hooting their car horns on nearby roads, they said.
On Wednesday, clashes broke out between police and opposition supporters after President Mahmoud Ahmadinejad was sworn in for a second term in office.
The opposition disputes the official result of the presidential election on 12 June, which gave Mr Ahmadinejad an overwhelming victory. After the poll, thousands of people took to the streets in the largest mass demonstrations in Iran since the 1979 Islamic Revolution.
Mr Ahmadinejad has received the backing of Supreme Leader Ayatollah Ali Khamenei, who says he was the rightful winner and that Iranians had "voted in favor of a fight against arrogance, to confront destitution and spread justice".
After taking his oath of office, Mr Ahmadinejad defended the official results and criticized Western powers' response to the disputed poll.