TEHRAN // Iranian security forces swept through the homes of the opposition leader Mehdi Karroubi and his family, arresting one of his sons and confiscating several documents, his website reported.
Meawhile, a top judiciary official warned that those who back the opposition movement will not be tolerated and will be considered as "anti-revolutionary".
Mr Karroubi's website, Sahamnews.org, reported three separate security operations against the cleric and his family members on Monday, in which his son Ali was arrested.
In one operation, security forces raided Mr Karroubi's house in Tehran and "took with them a large number of books and documents".
"The security forces confined Mrs and Mr Karroubi in separate rooms and then proceeded to search the home and replace all the locks," the website reported, adding that the fate of the cleric and his wife was unknown.
Mr Karroubi, reportedly under house arrest, is facing renewed pressure from authorities after his supporters and those of another opposition leader, Mir-Hossein Mousavi, held two demonstrations against the government last week.
The first demonstration, on Monday, resulted in deadly clashes with security forces in which two people were killed and several, including nine security personnel, were injured, opposition websites and officials reported.
The second demonstration, on Sunday, was crushed by a massive security presence in Tehran that prevented any large-scale gatherings from taking place.
Mr Karroubi and Mr Mousavi, former pillars of Iran's Islamic regime, have been defiant in their anti-government stance since they lost to Mahmoud Ahmadinejad in the June 2009 election that they claim was beset with fraud.
The recent protests by their supporters have infuriated supporters of the government, who have advocated complete isolation of the two men. In addition, some conservative politicians have demanded their execution.
But Mr Karroubi and Mr Mousavi, whose rebellion has rocked the Islamic regime, praised their supporters for Monday's gathering even as authorities moved in to cut their communication networks.
Sahamnews.org said that in a separate operation security forces arrested Mr Karroubi's third son, Ali, late on Monday.
"Security forces entered Ali Karroubi's house last night and arrested him. So far there are no reports on Ali Karroubi's fate," it said, adding that his wife, too, was briefly detained.
Sahamnews.org said that Ali was arrested for a few hours on February 11 last year and "brutally tortured."
The website also reported that the house of Mr Karroubi's other son, Hossein, too was raided on Monday but security forces "failed to arrest him as he was not present" there.
A top Iranian judiciary official meanwhile warned yesterday that anybody who followed the opposition leaders will now be treated as an "anti-revolutionary".
"If someone listens to the call of the seditionists today, that person is anti-revolutionary and should be treated as an anti-revolutionary," said Iran's prosecutor general, Gholam Hossein Mohseni Ejeie.
"Whoever wants to support the sedition leaders will be looked at as anti-revolutionary and will not be tolerated," Mr Mohseni Ejeie was quoted as saying by Fars news agency.
He said the line of distinction was now clear between followers of the revolution and those against it, but added that those who return to the regime's fold after apologising should be welcomed back.
