President Trump has repeatedly threatened to intervene if Iran's leaders, facing their biggest anti-government protests since 2022, use force against demonstrators.

Iran has warned it will retaliate if attacked by the US, as BBC sources and activists report hundreds of protesters have now been killed in an escalating government crackdown.

Israeli Prime Minister Benjamin Netanyahu and U.S. Secretary of State Marco Rubio spoke as Israel goes on high alert and Iran faces mounting anti-regime protests.

At least 538 people have been killed since demonstrations began two weeks ago, according to figures from the U.S.-based Human Rights Activists News Agency.

A statement from the group reads: “Live metrics show Iran is now in the midst of a nationwide internet blackout; the incident follows a series of escalating digital censorship measures targeting protests across the country and hinders the public's right to communicate at a critical moment.”

Violent crackdowns on anti-government protesters in Iran are drawing attention from Trump and condemnation from international human rights groups.

Dozens are reported to have been killed since anti-government protests began spreading across the country almost two weeks ago.

This wave of protests is unfolding against a backdrop fundamentally different from the past anti-regime movements, in the wake of June's 12-day war.