In this file photo taken on November 18, 2022 Iranians mourn in front of the coffins of people killed in a shooting attack, during their funeral in the city of Izeh in Iran s Khuzestan province. AFP
"UN Human Rights Chief Volker Turk says the rising number of deaths from protests in Iran, including those of two children at the weekend, and the hardening of the response by security forces, underline the critical situation in the country," spokesman Jeremy Laurence told reporters in Geneva.
"We urge the authorities to address people's demands for equality, dignity and rights, instead of using unnecessary or disproportionate force to suppress the protests," he said.
"The lack of accountability for gross human rights violations in Iran remains persistent and is contributing to the growing grievances."
His comments came after Iranian security forces on Monday intensified their crackdown in western Iran's Kurdish-populated regions, directly shooting at protesters, using heavy weapons and killing a dozen people over 24 hours, rights groups said.
The Kurdish-populated provinces of western and northwestern Iran have been hubs of protest since the death in custody of 22-year-old Kurdish woman Mahsa Amini on September 16, after she was arrested by morality police in Tehran.
The demonstrations sparked by Amini's death have become the most serious challenge to Iran's clerical regime since the 1979 revolution.
The UN rights office said more than 300 people had been killed since the protests began, including more than 40 children.
The Norway-based Iran Human Rights (IHR) group on Saturday put the death toll at at least 378 people.
There have been particularly intense anti-regime demonstrations in several towns in the last few days, rights groups say, largely sparked by the funerals of people said to have been killed by the security forces in previous protests.
Laurence said sources had told the rights office that more than 40 people had been killed in mainly Kurdish cities in the past week.
Two 16-year-old boys were among six killed over the weekend, he said.
"Significant numbers of security forces have also been deployed in recent days," he said, adding: "Overnight, we received reports of security forces responding forcefully to protests in several mainly Kurdish cities, including Javanrud and Saqqez."
Since the beginning, he said, "protesters have been killed in 25 of Iran's 31 provinces, including more than 100 in Sistan and Baluchistan".
Laurence voiced particular concern at "the authorities' apparent refusal to release the bodies of those killed to their families, or making the release of their bodies conditional on the families not speaking to the media or agreeing to give a false narrative on the cause of death."
He also pointed to the thousands of people "detained throughout the country for joining peaceful protests," adding that a growing number of Iranian celebrities and sports stars who had voiced support for the protests were being summoned and arrested.
Especially alarming, he said, was that so far six people connected to the protests had been handed death sentences.
"We call on the authorities to release all those detained in relation to the exercise of their rights, ... and to drop the charges against them," Laurence said.
"Our office also calls on the Iranian authorities to immediately impose a moratorium on the death penalty and to revoke death sentences issued for crimes not qualifying as the most serious crimes under international law."