Breaking tweets from a reliable twitterer:
Heavy Clashes at Vali Asr Sq.
Reports of Clashes at Dravzeh Shiraz, Isfehan.
Reports: Hundreds of People reaching infront of Tehran University... Clashes at Kargar St. still continues
Heavy Clashes at Karegar Shomali St, (Near Enghlab Sq.) Tear gas, Fire and blockage...
Hundreds of Protesters chanting against the regime infron of Ploytechnic University, Near Azadi Sq. (not conf)
Police used Teargas against people trying to push them back at Vanak Sq.
Clashes infront of Tehran Universi and VankSq.
Police Attacked People at Enghelab Sq.
And this time CNN is right on top of it:
Things are really heating up in the streets of Tehran. The crowds were in the hundreds according to our observers about a couple of hours ago. Now they say between 2,000 or 3,000 people, and we can confirm at least five clashes between security forces and protesters. This is happening in revolution square...very close to Tehran University. This is a protest to commemorate the 10-year anniversary of another protest ten years ago, a crack down that killed several students... The government had said don't come out or there will be a crackdown and that's exactly what's happening. ... [A]t least five clashes we can confirm between security forces and protesters.
Fresh but unverified footage: