A US naval strike group led by an aircraft carrier has deployed to Middle Eastern waters, the United States said Monday, as Tehran warned it was ready to hit back at any American attack launched in response to a crackdown on anti-government protests.
A US-based rights group said on Monday that it had confirmed the deaths of nearly 6,000 people in the wave of protests suppressed by Iran's security forces, but emphasized the actual toll could be several times higher.
The protests started in late December, driven by economic grievances, but turned into a mass movement against Tehran, with huge street demonstrations for several days from January 8.
But rights groups have accused authorities of quelling the movement with unprecedented violence, shooting into crowds of protesters under the cover of an internet shutdown that has now lasted 18 days -- the longest Iran has ever imposed.
The clerical leadership who took power after the 1979 revolution remains in place despite the protests, with many opponents of the system looking to outside intervention as the most likely driver of change.
US President Donald Trump has previously threatened to step in, saying last week that Washington was sending a "massive fleet" to the region "just in case".
The deployment of the USS Abraham Lincoln carrier strike group dramatically boosts American firepower in the region.
The United States backed and briefly joined Israel's 12-day war against Iran in June, and while Trump last week appeared to step back from his threats of new military intervention, he has never ruled the option out.
The Lincoln's strike group has arrived in the region, US Central Command said in a post on X, adding the ships were "currently deployed to the Middle East to promote regional security and stability".
- 'Regret-inducing response' -
Iran's foreign ministry warned on Monday of a "comprehensive and regret-inducing response to any aggression".
Ministry spokesman Esmaeil Baghaei said Iran was "confident in its own capabilities".
In apparent reference to the Lincoln, he added: "The arrival of such a battleship is not going to affect Iran's determination and seriousness to defend the Iranian nation."
Meanwhile, a new anti-US billboard has appeared in the central Enghelab Square in Tehran that appears to show an American aircraft carrier being destroyed.
"If you sow the wind, you will reap the whirlwind," its English-language caption reads.
State news agency IRNA quoted the commander of the Iranian navy Shahram Irani as saying on Monday: "Iran's naval power is not merely defensive but also acts as an anchor of stability in the region."
In Lebanon, Iran-backed group Hezbollah, whose capabilities and leadership were severely degraded in a war with Israel in 2024, organized a rally in support of Iran featuring an address by its leader Sheikh Naim Qassem, who warned "a war on Iran this time will ignite the region".
- Rising toll -
NGOs tracking the toll from the crackdown have said their task has been impeded by the internet shutdown, warning that confirmed figures are likely to be far lower than the actual number.
The US-based Human Rights Activists News Agency (HRANA) said it had confirmed that 5,848 people had been killed, including 209 members of the security forces. But the group added it was still investigating another 17,091 possible fatalities.
At least 41,283 people have been arrested, it said.
Giving their first official toll from the protests, Iranian authorities last week said 3,117 people were killed, the majority of whom it described as members of the security forces or innocent bystanders killed by "rioters".
Confirming that the internet blackout remains in place, monitor Netblocks said the shutdown was "obscuring the extent of a deadly crackdown on civilians".
"Gaps in the filternet are being tightened to limit circumvention while whitelisted regime accounts promote the Islamic Republic's narrative," it added.
Over the weekend, Persian-language TV channel Iran International, which is based outside the country, said more than 36,500 Iranians were killed by security forces from January 8 to 9, citing reports, documents and sources. It was not immediately possible to verify the report.
Activists have said that the Revolutionary Guards, a military force separate from the regular army with the mandate of keeping the revolution alive, took a frontline position in putting down the protests.
Italian Foreign Minister Antonio Tajani on Monday urged the European Union to list the Guards as a "terrorist organization", as Canada and the United States have done, saying the "the losses suffered by the civilian population during the protests demand a clear response".
