TEHRAN - Iranian hardline authorities accused opposition leaders on Thursday of links to foreign enemies and warned they would be shown no mercy unless they changed course.
The authorities have signaled they will tolerate no more protests after eight people, including a nephew of opposition leader Mirhossein Mousavi, were killed in fiery demonstrations on Sunday during the Shi'ite ritual of Ashura.
The opposition Jaras website said police fired two rounds of teargas to disperse a crowd of anti-government protesters who had gathered in a central Tehran square.
Independent verification was impossible because foreign media have been barred from covering protests directly.
Again we are warning the opposition leaders to immediately separate their path from the foreign enemies and the anti-revolution groups, the Intelligence Ministry said.
Otherwise they will be confronted with no mercy.
State television showed a group of pro-government demonstrators wearing white shrouds and carrying placards that read: We are ready to sacrifice our lives for the leader -- referring to Supreme Leader Ayatollah Ali Khamenei.
Iran has been rocked by protests since a disputed presidential election in June that gave President Mahmoud Ahmadinejad a second term.
The poll, which reformist leaders said was rigged, touched off the worst internal crisis in the Islamic Republic's 30-year history. The government denied any fraud in the voting.
Jaras said troops and armored vehicles were moving toward Tehran and that security forces had deployed in several city squares to foil a planned opposition rally. Officials denied that troops, which have not previously been used for crowd control, had been called in.
The authorities have often blamed foreign-backed forces for plotting to topple the clerical establishment, which is also locked in a standoff with the West over Iran's nuclear work.
A deadline set by the United States and its allies for Iran to accept a deal on nuclear fuel -- designed to calm fears that Tehran's atomic program is a cover for bomb-making -- expires on Thursday.
Iran, which may face tougher international sanctions in 2010, says its atomic work aims only to produce electricity.
Israel's ambassador to Washington told Reuters in an interview that U.S.-Israeli dialogue on Iran was focused on the issue of sanctions, and the two had not reached the point of discussing military action against the Islamic Republic.
Israel, which sees an existential threat from a nuclear-armed Iran, has not ruled out such action if diplomacy fails to end the dispute over Tehran's atomic program.
Hardline leaders in Iran have been calling this week for opposition leaders to be punished for fomenting unrest. The country's police chief warned Mousavi supporters on Wednesday to halt their illegal demonstrations or face harsh treatment.
Authorities have arrested at least 20 pro-reform figures, including three senior advisers to Mousavi, his brother-in-law and a sister of Iranian Nobel Peace Prize winner Shirin Ebadi.
Hundreds of thousands of people have turned out for government-organized demonstrations which saw calls for the execution of Mousavi and Mehdi Karoubi, both losing candidates in the June election won by Ahmadinejad.
Neither side has shown much appetite for compromise in the six months since then and confrontations look set to intensify, amid a rancorous flood of accusations and counter-charges.
On Tuesday, Abbas Vaez-Tabasi, a representative of Khamenei, said opposition leaders were 'mohareb' (enemies of god) fit for execution under Islamic law.
Prosecutor-General Qolamhossein Mohseni-Ejei urged them to repent or face charges of supporting apostates in defiance of God, the state-run newspaper Iran reported.
(Editing by Mark Trevelyan)