Iranian security forces have reportedly clashed with opposition supporters after huge crowds attended the funeral of one of the country's most influential dissident figures, Ayatollah Hossein Ali Montazeri.
Reports say the funeral passed off peacefully but afterwards opposition supporters began chanting slogans against the country's supreme leader, Ayatollah Khamenei.
Tens of thousands gathered on the streets of the Holy city of Qom to pay their respects to the late Grand Ayatollah, some carrying green signs - the colour of Iran's opposition.
Ayatollah Montazeri died of a heart attack on Saturday, aged 87.
He was viewed as the spiritual patron of an opposition movement that blossomed after a disputed presidential election in June.
He had described President Mahmoud Ahmadinejad's re-election a fraud.
Opposition leaders declared today a day of mourning.
The funeral was reportedly marred by brief clashes between hardline pro-government vigilantes and mourners.
Iranian websites reported that violence flared when security forces around the Grand Ayatollah's house clashed with stone throwing protestors.
However, none of these reports can be independently verified since foreign media have been banned from reporting directly on protests and had been told not to travel to Qom for the funeral.
So far there has been no official comment on the reports.
Ayatollah Montazeri was considered one of the chief architects of the Islamic Republic and was a student and close ally of Ayatollah Ali Khomenei, whom he was set to succeed.
But he fell from grace in the late 1980s after he became too openly critical of political and cultural restrictions and he resigned months before Ayatollah Ali Khomenei's death in 1989.
However over the next 20 years he continued to speak out in what he described as defence of freedom and justice.
