Thousands of Iranians have reportedly filled the streets of the capital, Tehran, and other cities as they reignite mass protests against the government.

Clashes have been reported around the capital, where witnesses say up to four people were killed when police and militia opened fire on the crowds.

The protests have been captured on videos and photos posted on Youtube and the social networking site, Twitter.

Al Jazeera's Nazanine Moshiri reports.