Iranian authorities have committed possible crimes against humanity through mass killings and arbitrary arrests of peaceful protesters. Civilians remain at risk of potential war crimes amid an effectively collapsed ceasefire between the US and Iran.

BACKGROUND:

On 28 February the United States (US) and Israel launched a joint offensive against Iran, affecting over 20 of Iran’s 31 provinces. The aerial attacks triggered Iran to launch widespread retaliatory attacks, targeting US military bases in Bahrain, Kuwait, Qatar and Saudi Arabia, as well as targeted or indiscriminate strikes on civilian infrastructure across the region. In the first week of the offensive, the death toll in Iran surpassed 1,000 people. Over 160 people were killed when an elementary girls’ school in southern Iran was struck by a reported US missile, prompting UN experts to call for an investigation into possible war crimes. Approximately 3.2 million people were temporarily displaced inside Iran during hostilities.

The US-Israeli offensive and Iran’s retaliatory strikes drew condemnation from several UN experts, who stressed that international law must not be selectively applied. On 11 March the UN Security Council (UNSC) adopted a resolution co-sponsored by 135 countries that condemned Iran’s attacks neighboring Middle East states but stopped short of denouncing US-Israeli strikes. A month later, the UN Independent International Fact-Finding Mission on the Islamic Republic of Iran (FFMI) stressed that US and Israeli strikes had “caused irreparable harm and long-term consequences for Iranian civilians” and denounced rhetoric by senior US officials that dismissed their obligations under international law.

On 8 April a temporary two-week ceasefire agreement between the US and Iran – mediated by Pakistan – took effect and was subsequently extended. Negotiations for a permanent agreement are pending, covering issues such as the Strait of Hormuz shipping route, Iran’s nuclear activities, sanctions relief and other conflicts in the region. The agreement follows a period marked by unilateral US military action, including strikes on Iran in June 2025, purportedly to destroy the country’s nuclear facilities.

Prior to the offensive, in December 2025, demonstrations erupted across Iran in response to a deepening economic crisis following the collapse of the national currency and soaring inflation. The demonstrations evolved into a nationwide movement opposing the government and its repressive policies. Iranian authorities responded with a violent crackdown, during which police units and the Islamic Revolutionary Guard Corps (IRGC) committed unlawful use of force and mass arbitrary arrests.

The FFMI reviewed footage showing security forces opening fire on protesters, as well as evidence of unlawful use of force in ethnic minority provinces, which have historically endured some of the most brutal crackdowns. Thousands of protesters were killed and detained, though some estimates suggest the true figure may reach tens of thousands. Officials also used dangerous rhetoric against protesters, labeling them “terrorists” and describing “rioters” an “enemy of God,” an offense punishable by death. Global condemnation following reports of imminent executions compelled Iran’s foreign minister to state that executions would not take place, while the judiciary has vowed to accelerate trials. After partially lifting a near-total internet shutdown imposed on 8 January, Iranian authorities intermittently reinstated these measures following US-Israeli strikes.

International response to the crackdown varied. The US government threatened unilateral military action while key regional allies urged restraint, warning of broader destabilization. The United Kingdom, Canada, France and the European Union, among others, called on the Iranian authorities to uphold their “responsibility to protect their own population.”

The recent crackdown is part of a decades-long pattern of lethal force used against protesters challenging repression and deteriorating living conditions. During the 2022-2023 “Women, Life, Freedom” nationwide protests, security forces similarly wielded unnecessary and disproportionate force, killing at least 500 people. In March 2023 the UN Special Rapporteur on the situation of human rights in the Islamic Republic of Iran concluded that the state’s widespread clampdown may amount to crimes against humanity, including murder, imprisonment, enforced disappearances, torture, rape and sexual violence and persecution. The following year, the FFMI concluded that Iranian authorities perpetrated the crime against humanity of gender persecution.

Iran is also among the countries with the highest number of executions annually and has a history of unlawful arbitrary executions. In 2025 Iran’s use of capital punishment almost doubled from 2024. According to Amnesty International, at least 2,159 individuals were executed, marking the highest number of executions in decades. The UN High Commissioner for Human Rights has stressed that “the scale and pace of executions suggest a systematic use of capital punishment as a tool of State intimidation, with disproportionate impact on ethnic minorities and migrants.”

For nearly five decades, Iran has been subject to a complex and evolving sanctions regime – largely led by the US – that has devastated living standards for Iranians. This situation was further exacerbated by the reimposition of significant US economic sanctions in 2018. Human rights experts and organizations have warned that unilateral coercive measures undermine Iranians’ basic human rights and that sanctions threaten the economy and push millions of Iranians into poverty.

RECENT DEVELOPMENTS:

Despite extensions to the initial ceasefire, intermittent clashes between US and Iranian vessels in the Strait of Hormuz occurred. Military strikes recommenced in mid-June amid reports of US intentions to pressure Iran on the terms of the agreement. The US and Iran signed a memorandum of understanding (MoU) on 17 June establishing a framework for ending the war and extending the ceasefire by another 60 days. However, hostilities renewed between the two parties by 7 July, with US President Donald Trump declaring the MoU “over,” and notifying US Congress of renewed war with Iran.

After US-Israeli strikes reportedly killed Iran’s supreme leader, Ayatollah Ali Khamenei, and several other senior officials, his son, Mojtaba Khamenei, was appointed as his successor. Despite the leadership upheaval, authorities have continued efforts to deter public dissent. At least 21 individuals have been executed since 28 February, and more than 4,000 have been arrested on charges related to national security.

On 11 March the FFMI reported “unprecedented levels” of state repression not seen since the 1979 revolution. The FFMI asserted that previously established patterns of violations by Iranian authorities, including those that may amount to crimes against humanity, “not only remain present but also continue to evolve and deepen.”

ANALYSIS:

Iranians face continued protection threats amid the effective collapse of the ceasefire and MoU between Iran and the US. While most UN member states have condemned Iran’s counterattacks, they have largely refrained from denouncing US-Israeli operations, reflecting a selective application of international law. The failure to condemn or address unlawful and unilateral coercive actions enables ongoing abuses in Iran and throughout the region.

While the death of Ali Khamenei marks the end of his rule, Iran’s system of power remains intact. Persistent repressive measures by authorities, together with the succession of his son, who has been closely linked to the IRGC, underscore that punitive structures extend beyond a single individual. Iran’s structural suppression of dissent risks blanket criminalization of opposition. Thousands remain detained, raising concerns about due process rights and torture.

Longstanding impunity has shielded Iranian authorities from accountability, emboldening repeated cycles of widespread state violence against the population. Iran’s economic crisis is deeply tied to entrenched abuses.

RISK ASSESSMENT:

• • • Collapsed ceasefire, risking a return to large-scale attacks between the US and Iran.
    • Widespread and coordinated unlawful use of force to suppress dissent, alongside legal and institutional infrastructure designed to legitimize repression.
    • Increasing use of the death penalty, including for unlawful arbitrary executions.
    • Institutionalized discrimination against women, girls and minorities.
    • Ongoing impunity for cycles of deadly crackdowns against protesters, including crimes against humanity.

NECESSARY ACTION:

States must condemn all violations of international law and the UN Charter. States should avoid unlawful participation in military actions, push for the negotiation of a permanent ceasefire and center the aspirations of the Iranian people.

Iranian authorities must refrain from intimidation tactics to repress protests, release protesters detained for exercising their human rights and ensure compliance with international human rights standards. Access to the internet and communication services must be fully restored.

The international community must address Iran’s longstanding impunity for serious human rights violations and atrocities in a coordinated, principled manner that advances justice and accountability. This includes pursuing criminal accountability for Iranian officials allegedly responsible for crimes against humanity, including through universal jurisdiction. UN Human Rights Council members should ensure the FFMI is adequately resourced. The UNSC should maintain Iran on its agenda and support a referral to the International Criminal Court.