Iran restricted internet and phone access overnight in an escalation of its attempt to quell protests, after thousands of demonstrators appeared to take to the streets of Tehran and across the country.

The death toll since the unrest began late last year has risen to 42, according to the US-based Human Rights News Agency, which tracks protests and the activities of political activists in Iran. UK broadcaster BBC said it had independently confirmed at least 21 of the fatalities.

The demonstrations have escalated into the most serious challenge to 86-year-old Supreme Leader Ayatollah Ali Khamenei and his theocratic government since a nationwide uprising in 2022. They started in Tehran’s Grand Bazaar on Dec. 28 after a slump in the value of Iran’s currency to record lows, worsening a cost-of-living crisis in the sanctions-hit economy. 

The OPEC member’s situation has been worsened by corruption and by oil prices falling heavily in the past year. 

Khamenei said Friday his country won’t back down against “mercenaries” or those who engage in “vandalism,” state-run Press TV reported.

The unrest began disrupting air travel in and out of the country. Non-Iranian airlines canceled all Friday flights between Tehran and Istanbul as of 11:30 a.m. local time, with additional delays and cancellations in Dubai, according to airport websites.

Monitoring group Netblocks on Thursday reported a nationwide shutdown of the internet in Iran. Various efforts by Bloomberg to reach individuals in the country by landline and mobile phone failed. One Tehran resident said phone calls weren’t working at all or were cutting in and out, and SMS messages were heavily restricted.

Iranian authorities frequently resort to such tactics during periods of unrest as they seek to prevent people sharing images of state violence against civilians.

Even so, videos posted on X and Instagram overnight showed large numbers of people gathered on several major streets in different areas of Tehran, the capital. One clip appeared to show hundreds in a central thoroughfare in the Karim Khan neighborhood chanting “death to the dictator.”

In the city of Isfahan, protesters pulled down the entrance sign of a branch of state TV — which has downplayed the protests — while flames burned in the background.

Bloomberg hasn’t been able to verify the videos.

In at least one post, the chant of “Long live the Shah” can be heard. That’s a reference to the late Shah of Iran — deposed during the 1979 revolution — and his son, Reza Pahlavi, who lives in exile in the US. 

Pahlavi, 65, says he wants to lead a transition to democracy in Iran and has urged Iranians to protest. On X, he called on them to “make the crowd even larger” on Friday evening.

US President Donald Trump on Thursday called Pahlavi a “nice person” but said he wasn’t sure that it would be “appropriate” to meet him. The rule of Pahlavi’s father was widely despised and its overthrow gave birth to the Islamic Republic.

“I think that we should let everybody go out there, and we’ll see who emerges,” Trump said in an interview. He reiterated warnings to Iran against killing protesters, saying “if they do that, they’re going to have to pay hell.”

In an apparent response, Khamenei said Trump should “focus on running own country if capable” and that his hands are “stained with blood” after the US and Israeli airstrikes on Iran in June.

State TV said Friday “terrorist elements” linked to supporters of the monarchy and the outlawed Mojahedin-e-Khalq opposition group set fire to vehicles, banks and a metro station during what it described as “riots.” Several people died, it said, without elaborating.

What Bloomberg Economics Says…“A collapse appears unlikely for now. Iranians are frightened of chaos, having seen it wreak havoc in neighboring Iraq and Syria. The government remains in control and could still crack down hard. But the risks rise the longer protests persist — and would jump sharply if war breaks out.”

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