The UN human rights chief has said he is alarmed by the rise in executions in Iran, with capital punishment continuing to be used "to instil fear among the population and suppress dissent".

Volker Türk said at least 56 people had been executed on national security-related charges since 19 March, including 27 in cases linked to January's nationwide anti-government protests.

More than 100 others were at risk of execution on similar charges, while executions for drug-related offences were also continuing at an alarming rate, he added.

Iran is thought to be the world's second-most prolific executioner after China. Last year, it put to death at least 2,159 people, according to Amnesty International.

The human rights group said that was the highest figure on record since 1981 and included 45 executions of suspected dissidents on national security-related charges.

Activists have warned that Iranian authorities might make greater use of executions against their opponents following January's protests, during which thousands of demonstrators were killed and tens of thousands were detained, and the US-Israeli war with Iran on 28 February.

In a statement, Türk urged Iranian authorities to halt all executions and move toward the abolition of the death penalty, saying that "such punishment has no place in our world".

As well as expressing alarm at the rise in executions, he said the persistent lack of fair trial and due process guarantees was "deeply troubling", with confessions allegedly obtained under torture and other ill-treatment.

"Several executions have reportedly been carried out in public. Some have reportedly been carried out only weeks after arrest," he added.

"Twelve defendants were reportedly sentenced to death following a single three-hour closed-door hearing."

There was no immediate comment from the Iranian government. But it has previously defended the use of the death penalty, saying it is limited to only "the most severe crimes".

On Monday, Iran's judiciary said it executed two men convicted of spying for Israel.

Omid Behzad and Pouria Safvat were accused of sending coordinates, images and other information on sensitive military, law enforcement and security sites to Israel's Mossad foreign intelligence service during the current war and the 12-day conflict in June 2025, according to the judiciary's Mizan news agency.

Last week, 19-year-old Arvin Kheirkhahan was executed after being convicted of the security-related charge of "enmity against God" over his alleged role in January's unrest, Iran's Human Rights Activists News Agency (HRANA) reported, citing a source close to his family.

Another two men arrested during the protests, Abolfazl Sepahi Badjani and Amirhossein Safari Hosseinabadi, were executed in public in a square in Isfahan, according to HRANA.

They were among 12 people convicted of several charges, including "enmity against God" and "corruption on Earth", in connection with the killing of four law enforcement officers on 8 January.

Two of their fellow defendants, Erfan Esfandiari and Gol Mohammad Mohammadi, were executed on 19 July.

UN human rights experts said the 12 were sentenced to death "in one hearing, in a closed courtroom and without clarity as to each defendant's individual responsibility", which violated established fair trial standards.