A top US senator said today Iran's supreme leader has pushed the conflict there toward a "very brutal outcome", as it was confirmed that at least 17 people are dead.
Indiana Republican Senator Richard Lugar, one of the Senate's most respected voices on foreign affairs, criticised Ayatollah Ali Khamenei for refusing to give in to demonstrators' demands for a re-run of the disputed June 12 election that returned President Mahmoud Ahmadinejad to office.
Mr Lugar told CNN that has laid the ground for a "potentially very brutal outcome at the end of the day".
Iran has imposed strict controls on foreign media covering the unrest, saying correspondents cannot go out into the streets to report.
Reporters Without Borders said 20 journalists were arrested over the past week. The BBC said today that its Tehran-based correspondent, Jon Leyne, had been asked to leave the country. The BBC said its office remained open.
Today, Iranian Foreign Minister Manouchehr Mottaki held a news conference where he rebuked Britain, France and Germany for raising questions about reports of voting irregularities in hardline Mr Ahmadinejad's re-election - a proclaimed victory which has touched off Iran's most serious internal conflict since the revolution.
Mr Mottaki accused France of taking "treacherous and unjust approaches". But he saved his most pointed criticism for Britain, raising a litany of historical grievances and accusing the country of flying intelligence agents into Iran before the election to interfere with the vote. The election, he insisted, was a "very transparent competition".
That drew an indignant response from Foreign Secretary David Miliband, who "categorically" denied Britain was meddling. "This can only damage Iran's standing in the eyes of the world," Mr Miliband said.
An eerie calm settled over the streets of Tehran today as state media reported at least 10 more deaths in post-election unrest and said authorities arrested the daughter and four other relatives of ex-President Hashemi Rafsanjani, one of Iran's most powerful men.
The reports brought the official death toll for a week of boisterous confrontations to at least 17. State television inside Iran said 10 were killed and 100 injured in clashes yesterday between demonstrators and black-clad police wielding truncheons, tear gas and water cannons.
Iran's regime continued to impose a blackout on the country's most serious internal conflict since the 1979 Islamic Revolution.
The New-York based International Campaign for Human Rights in Iran said scores of injured demonstrators who had sought medical treatment after yesterday's clashes were arrested by security forces at hospitals in the capital.
It said doctors had been ordered to report protest-related injuries to the authorities, and that some seriously injured protesters had sought refuge at foreign embassies in a bid to evade arrest.
"The arrest of citizens seeking care for wounds suffered at the hands of security forces when they attempted to exercise rights guaranteed under their own constitution and international law is deplorable," said Hadi Ghaemi, spokesman for the campaign, denouncing the alleged arrests as "a sign of profound disrespect by the state for the well-being of its own people".
"The government of Iran should be ashamed of itself. Right now, in front of the whole world, it is showing its violent actions," he said.
State-run Press TV reported that Rafsanjani's eldest daughter, Faezeh Hashemi, and four other family members were arrested late last night. It did not identify the other four.
Last week, state television showed images of Ms Hashemi, 46, speaking to hundreds of supporters of opposition candidate Mir Hossein Mousavi. After her appearance, hardline students gathered outside the Tehran prosecutor's office and accused her of treason, state radio reported.
Mr Rafsanjani, 75, has made no secret of his distaste for Mr Ahmadinejad, whose re-election victory in a June 12 vote was disputed by Mr Mousavi. Mr Ahmadinejad has accused Mr Rafsanjani and his family of corruption.
The influential Mr Rafsanjani now heads two very powerful groups. The most important one is the Assembly of Experts, made up of senior clerics who can elect and dismiss the supreme leader. The second is the Expediency Council, a body that arbitrates disputes between parliament and the unelected Guardian Council, which can block legislation.
Today's state media reports said rioters set two gas stations on fire and attacked a military post in clashes yesterday. They quoted the deputy police chief claiming officers did not use live ammunition to dispel the crowds.
Iran has also acknowledged the deaths of seven protesters in clashes on Monday.
Amnesty International cautioned that it was "perilously hard" to verify the casualty tolls.
The BBC's correspondent in Tehran has been ordered to leave the country, a BBC spokesman confirmed on condition of anonymity in line with company policy.
The Fars news agency said today that Jon Leyne will have to leave Iran within 24 hours, and that Iranian officials have accused him of "dispatching fabricated news and reports, ignoring neutrality in news, supporting rioters and trampling the Iranian nation's rights".
Iranian authorities have arrested 23 journalists and bloggers since post-election protests began a week ago, according to a media watchdog that says reporters are a "priority target" for Iran's leadership.
Among those arrested was the head of the Association of Iranian Journalists, Reporters Without Borders said today.
"It's becoming more and more problematic for journalists," said Benoit Hervieu of the Paris-based group, also known by its French acronym RSF.
The group released a list of 23 Iranian journalists, editors and bloggers arrested since June 14, and says it has lost contact with several others believed detained or in hiding. Mr Hervieu said RSF verified each arrest via its network of reporters and activists in Iran. No foreign journalists were on the list.
The reasons behind the detentions remain unclear.
Iran's authorities have long kept a close eye on local and international media operating in the country, and clamped down as protests engulfed Tehran last week over the June 12 presidential election, the biggest challenge to the cleric-led government in 30 years. President Mahmoud Ahmadinejad was declared the landslide winner, but supporters of reformist challenger Mir Hossein Mousavi say fraud was widespread.
Authorities have banned foreign media from reporting from the street and allow only phone interviews and information from officials sources such as state TV. Many websites have been blocked. Iran is particularly sensitive about news reports, blogs and internet reports in Farsi.
"The regime has been visibly shaken by its own population and does not want to let this perception endure," RSF said in a statement.
Ali Mazroui, the head of the Association of Iranian Journalists, was arrested this morning, RSF said. Overnight, husband-and-wife Bahaman Ahamadi Amoee and Jila Baniyaghoob were arrested by plainclothes officers who searched their home, RSF said.
Ms Baniyaghoob edits a news web site that focuses on women's rights, and her husband writes for various pro-reform publications.
Also detained is Mohammad Ghochani, editor of Etemad Meli, owned by opposition presidential candidate Mehdi Karoubi.
Others detained include a blogger known as the "Blogging Mullah", a cartoonist, a TV producer, the publisher of several newspapers, a disabled former newspaper editor and a business reporter.
Nakhle Elhage, news director at Dubai-based Al-Arabiya television network, said authorities told them their activities have been suspended until further notice but did not ask their resident correspondent Diaa al-Nasseri - an Iraqi - to leave.
Last Sunday, Al Arabiya in Tehran was told by the authorities to suspend their activities for one week.
RSF says that, even before the election, Iran held more journalists and cyber-dissidents in jails than any other country in the Middle East.
Mr Hervieu said blogs, Twitter, YouTube and other internet methods are the only way most people can convey information from the street. But the use of anonymity by blog posters trying to avoid repercussions makes information difficult to verify.
Many of those posting "are both spectators and activists," blurring lines of impartiality, he said.
He said small digital cameras passed from activist to activist and then to a foreign colleague or news organisation are helping spread images, though their provenance is not always clear.
He noted the example of the much-viewed amateur video on YouTube, showing dozens of Iranians running down a street and shouting "Allahu Akbar" after police fired tear gas.
AP Executive Editor Kathleen Carroll said last week that, when controls are imposed, "we work with those restrictions, keeping in mind our ultimate goal is to be able to do our jobs as journalists".
Reporters were also restricted during the 1979 Iranian Revolution, which saw the installation of the Islamic regime in power today.
State-run Press TV tonight reported that Mr Rafsanjani's eldest daughter, Faezeh Hashemi, and four other unidentified family members were arrested late yesterday. This evening, it said the four others had been released but that Ms Hashemi remained in detention.