Iranian students defy security clampdown and protest

Iranian students have defied a security clamp down to stage anti-government protests throughout the country, witnesses and opposition groups say.

Unconfirmed reports say about a dozen people have been arrested, including some at Tehran University in the capital.

Last year's protests led to clashes with security forces as students lashed out over the disputed re-election of President Mahmoud Ahmadinejad.

This year's protests appear smaller, and there are no reports of violence.

Pro-government rallies have also been held across the country.

(Pictures filmed by Iranian student)