Iran's hard-line rulers - who have also tried to capitalize on the uprising against their regional rivals in Egypt's U.S.-allied regime - are seeking to deprive their own opponents at home of any chance to reinvigorate a movement swept from the streets in a heavy military crackdown.
The leader confined to his home, Mahdi Karroubi, had joined Iran's other top opposition figure, Mir Hossein Mousavi, in asking the government for permission to hold a Feb. 14 rally in support of the uprisings in Egypt and Tunisia.
State Prosecutor Gholam Hossein Mohseni Ejehi rejected the demand on Wednesday and warned of repercussions if the rally takes place. Instead, he said those seeking to show solidarity with Egyptian protesters should join a state-organized rally marking the 32nd anniversary of Iran's 1979 Islamic Revolution on Friday.
Security officers were stationed at the entrance of Karroubi's house in Tehran on Thursday and prevented relatives, including his children, from meeting him, according to Karroubi's website, sahamnews.org. A security official informed Karroubi that the restrictions would remain in place until after Feb. 14.
He and Mousavi are the main political adversaries of the hard-line leadership. Both men ran against President Mahmoud Ahmadinejad in an election in June 2009 that the opposition believes was heavily rigged. Mousavi, who campaigned on a platform calling for social and political reforms, maintains he was the rightful winner and that Ahmadinejad was declared the winner through massive vote fraud.
White House national security spokesman Tommy Vietor said in a statement Thursday the arrest underscored the hypocricy of Iran's leadership.
"For all of its empty talk about Egypt, the government of Iran should allow the Iranian people the same universal right to peacefully assemble and demonstrate in Tehran that the people are exercising in Cairo," he said.
The protests that swept Iran in the months after the vote grew into a larger movement opposed to Iran's ruling system. It was the biggest challenge faced by Iran's clerical leadership since it came to power in the 1979 revolution that toppled the U.S.-backed shah.
Hundreds of thousands peacefully took to the streets in support of Mousavi, and some powerful clerics sided with the opposition.
But a heavy military crackdown suppressed the protests, and many in the opposition - from midlevel political figures to street activists, journalists and human rights workers - were arrested. The opposition has not been able to hold a major protest since December 2009.
The opposition says more than 80 demonstrators were killed in the turmoil. The government, which puts the number of confirmed deaths at 30, accuses opposition leaders of being "stooges of the West" and of seeking to topple the ruling system through street protests.
Karroubi and Mousavi have compared the unrest in Egypt and Tunisia with their own postelection protest movement. Mousavi said Iran's demonstrations were the starting point but that all the uprisings aimed at ending the "oppression of the rulers."
A senior commander of the Revolutionary Guard, the most lethal weapon used in crushing Iran's 2009 protests, had a chilling warning for any attempt by the opposition to rally supporters on Feb. 14.
"Seditionists are no more than a corpse. We will severely crush any of their movements," the official IRNA news agency quoted Hossein Hamedani as saying.
A separate report posted on Karroubi's website Thursday said one of his aides, Taqi Rahmani, was arrested at midnight by security agents who entered his house. No reason has been given for the arrest.
The liberal-minded Rahmani has spent more than 17 years in jail since Iran's revolution for his critical writings and political activities against ruling hard-line clerics.