Despite threats by the governor of Teheran province that any new demonstrations would be "smashed," hundreds of young men and women chanted "death to the dictator," took the streets of Iran on Thursday, confronting police wielding batons and firing tear gas in the capital. The supporters of opposition leader Mir Hossein Mousavi have called for new demonstrations in the Iranian capital and several other cities in a bid to revive street action after police, Revolutionary Guards and Basij militiamen crushed the dramatic mass protests that erupted over Iran's disputed June 12 presidential election. There has not been a major protest in 11 days since the crackdown. Teheran governor Morteza Tamaddon warned that any new march would meet the same fate. "If some individuals plan to conduct anti-security moves through listening to a call by counter-revolutionary networks, they will be smashed under the feet of our aware people," he said, according to the state news agency IRNA in a report late Wednesday. Video: A tribute to Neda "Enemies are angry about the calm after the post-election plots and are trying to damage the peace through foreign, counter-revolutionary and notorious networks," Tamaddon said, adding that public awareness would defuse all "plots" and the government would "strongly" provide security. Thursday afternoon, a stepped-up number of uniformed policemen along with plainclothes Basiji militiamen stood at intersections all along Revolution Street and at nearby near Teheran University, some of the sites where protests were called. Still, a group of around 300 young people gathered in front of Teheran University and began to chant, "Death to the dictator," witnesses said. Many of them wore green surgical masks, the color of Mousavi's movement. Police charged at them, swinging batons, but the protesters fled, then regrouped at another corner and resumed chanting, the witnesses said. Police chased them repeatedly as the protesters continued to regroup, the witnesses said, speaking on condition of anonymity because they feared government retribution. Within an hour, the number of protesters grew to about 700 and marched toward the gates of Tehran University, the witnesses said. A line of policemen blocked their path, but they did nothing to disperse the gathering as the protesters stood and continued to chant, the witnesses said. At another location, on Valiasr Street, around 200 protesters gathered, and police fired tear gas to disperse them, but the demonstrators sought to regroup elsewhere, the witnesses said. Soon after the confrontations began, mobile phone service was cut off in Tehran, a step that was also taken during the height of the post-election protests to cut off communications. Mobile phone messaging has been cut in the country for the past three days. The government also closed down universities and called a government holiday on Tuesday and Wednesday, citing a heavy dust and pollution cloud that has blanketed Teheran and other parts of the country this week. Many saw the move as aimed at keeping students away from campuses where protests could be organized. Thursday is a weekend day in Iran, and many people used the surprise long holiday to travel to other cities where weather was better. The calls for protest have been circulating for days on social networking Web sites and other pro-opposition Web sites. The protests have been called to coincide with the anniversary Thursday of a 1999 attack by Basij on a Teheran University dorm to stop protests in which one student was killed. Mousavi and his pro-reform supporters say he won the election and that official results showing a landslide victory for incumbent Mahmoud Ahmadinejad are fraudulent. Hundreds of thousands marched in the streets for days following the election, demanding a new vote. Supreme leader Ayatollah Ali Khamenei declared the results valid after a partial recount and warned that unrest would not be tolerated. In the crackdown that followed, at least 20 protesters and 7 Basijis were killed in the crackdown and at least 1,000 people were arrested. Police say most have since been released, but security forces have continued to round up dozens of activists, journalists and bloggers.