This story so far has been reported here, here and here.
Defeated Iranian presidential candidate Mehdi Karroubi has alleged that several male and female protesters held behind bars have been savagely raped, according to a document obtained by AFP on Monday.
"A number of detainees have said that some female detainees have been raped savagely. Young boys held in detention have also been savagely raped," Karroubi said in a letter to powerful cleric Akbar Hashemi Rafsanjani.
"The young boys are suffering from depression and serious physical and mental damage since their rapes."
Iran hit back on Monday at Western criticism of the mass trials of election protesters, saying it would strongly resist such "foreign intervention" in its domestic affairs.
Iran has put around 110 people in the dock over the protests unleashed since the re-election of President Mahmoud Ahmadinejad in June, including a French woman lecturer and two local employees of the British and French embassies.
Britain, France and the European Union have condemned what Washington has branded "show trials."
Iranian foreign ministry spokesman Hassan Ghashghavi said the Western criticism was "illegal and surprising," and said statements by the embassy employees in court smacked of foreign meddling.
"The comments made by Iranians working here is an example of foreign intervention in Iran's domestic affairs. We will strongly stand against any intervention," he said, the IRNA news agency reported.