Iranian security forces stormed a series of opposition offices today, rounding up at least seven prominent anti-government activists in a new crackdown against the country's reformist movement, opposition websites and activists reported.
The arrests came a day after at least eight protesters were killed during anti-government marches marking Shiite Islam's most important observance.
The bloodshed, some of the heaviest in months, drew an especially harsh condemnation from one opposition leader, who compared the government with the brutal regime that was ousted by the Islamic Revolution three decades ago.
Today's developments were sure to deepen antagonism between the government and the reform movement, which has repeatedly shown resilience in the face of repeated crackdowns since June's disputed presidential election.
Mahdi Karroubi, an opposition leader who ran in the June election, posted a statement on an opposition website asking how the government could spill the blood of its people on the Shiite sacred day of Ashoura. He said even the former government of the hated shah respected the holy day.
"What has really happened that (caused the ruling system) spilled the blood of people on the day of Ashoura and gets a group of savage individuals confronting people?" he told the Rah-e-Sabz website. The shah, who was overthrown in 1979, was widely hated, and comparing a rival with the shah is a serious, though common, insult in Iranian politics.
Opposition websites reported at least seven arrests today. The Parlemannews site said three top aides to opposition leader Mir Moussavi were arrested, including his top adviser, Ali Riza Beheshti.
Security forces also stormed a foundation run by reformist former president Mohammad Khatami and arrested two people, a foundation official said. The Baran Foundation works to promote dialogue between civilisations.
In another move, former foreign minister Ebrahim Yazdi and human rights activist Emad Baghi were arrested, according to the Rah-e-Sabz website. Yazdi, who served as foreign minister after the 1979 Islamic revolution, is now leader of the banned but tolerated Freedom Movement of Iran.
The arrests could not be independently confirmed.
Sunday's violence erupted when security forces fired on stone-throwing protesters in the centre of Tehran. Opposition websites and witnesses said five people were killed, but Iran's state-run Press TV, quoting the Supreme National Security Council, said the death toll was eight. It gave no further details.
The dead included a nephew of Mousavi, according to Mousavi's website, Kaleme.ir. Police denied using firearms.
The street chaos coincided with commemorations of Ashoura, fuelling protesters' defiance with its message of sacrifice and dignity in the face of coercion. The observance commemorates the 7th-century death in battle of one of Shiite Islam's most beloved saints.
The clashes marked the bloodiest confrontation since the height of unrest in the weeks after June's election. The opposition says Ahmadinejad won the election through massive vote fraud and that Mousavi was the true winner.