By IANS,
Tehran : Iranian security forces fired teargas shells to disperse protesters who had gathered at a Tehran square in support of demonstrations in Egypt and Tunisia, while opposition leader Mir Hossein Mousavi was placed under house arrest.
Clashes were reported to have taken place at the Enghelab Square in Tehran between security forces and protesters.
The demonstration was called Monday by opposition leaders Mir-Hussein Mousavi and Mehdi Karroubi, in support of the Egyptian and Tunisian uprisings.
People in separate groups, silently and without chanting slogans, moved towards the Azadi Square, but security forces chased them away, Xinhua reported.
Gatherings were also reported from Imam Khomeini Square, Haft-e-Tir Square and on Karim Khan and Vali-e-Asr streets.
According to AKI news agency, opposition leader Mir Hossein Mousavi was placed under house arrest.
His official website said the move was made to keep him from taking part in a demonstration in solidarity with the pro-democracy protests that toppled Eyptian president Hosni Mubarak.
Police have taken similar precaution against fellow leader Mehdi Karroubi.
Authorities have also blocked websites and satellite news channels in an effort to disrupt communications that could help organise protests.