Violence erupted (evidently on June 20) in other Iranian cities besides Tehran, but it is more difficult to get information. A report (from reliable source that must remain anonymous):
I received communication from Shiraz that there have been clashes in different parts of the city. What is notable about Shiraz is that the security forces have sometimes lashed out randomly at people who might only look like protesters. An eyewitness confirmed this report.
This video is posted with the text below (including incorrect date):
several people have been wounded and killed by POLICE during the Anti Iranian government protest against election fraud in Iran, Shiraz city, including a man which has been allegedly killed, on Saturday 21 June 2009