Thousands of opposition supporters gathered after Friday Prayers at Tehran University today. These are the first images to emerge from the event.

We’re updating this post throughout the day.

The size of the protest was impressive.

Footage shot after the police used tear gas to disperse the crowds. Protestors start fires in the hope of dispersing the gas. Posted on Facebook.

From here we can see the gates of Tehran University, where Fridays Prayers are taking place.

The protestors chant "Mousavi, Mousavi", "Allah Akbar", "down with the government", "release the political prisoners", "we might die but we'll never give up" and "down with Russia".

Video posted on Facebook. Our Observers say that the video appears to have been filmed today.