Iran's state news agency has reported that six people have gone on trial in Tehran for taking part in widespread protests following the disputed presidential election in June.
The IRNA news agency reports that one of the defendants is the student activist and human rights campaigner Abdollah Momeni.
Iran last month began four mass trials over post-election events against more than 100 people, including senior reformers and former government officials, charged with orchestrating opposition protests in a bid to undermine the Islamic Republic.
The opposition has denounced the court sessions as "show trials". Reformist former president Mohammad Khatami says trial confessions by moderates were made in "extraordinary conditions" and were invalid.
'False' internet reports provoked unrest
An indictment read out at the trial of the latest six appeared to focus on "false reports" spread via the internet in a bid to stir unrest.
The election and its turbulent aftermath plunged Iran into deep internal crisis. Rights groups say thousands of people, including senior pro-reform figures, were arrested after the poll, though most have been freed.
The moderate opposition says the 12 June poll was rigged to secure President Mahmoud Ahmadinejad's re-election. The authorities deny it.
Hardliners have portrayed the opposition protests as a foreign-backed bid to undermine the Islamic government system.