Dozens of protesters have been killed or wounded after Iranian security forces opened fire following Friday prayers in the country's south-east, activists said.
The demonstrators were part of an anti-government movement raging since September, which was sparked by the death in custody of Mahsa Amini — a 22-year-old Iranian woman of Kurdish origin — and has now snowballed into wider issues around women's freedoms.
Campaigners had called for nationwide demonstrations this week in solidarity with Kurdistan, which along with Sistan-Baluchistan, where Friday's shooting took place, has borne the brunt of Iran's deadly protest crackdown.
“Kurdistan, Kurdistan, we will support you,” protesters were heard chanting on Friday in a video from the Sistan-Baluchistan capital Zahedan, one of the few Sunni-majority cities in predominantly Shiite Iran.
“Kurds and Baluchs are brothers, thirsting for the leader's blood,” they sang in other unverified footage posted on social media, in reference to Iran's supreme leader Ayatollah Ali Khamenei.
Activists said later that security forces had opened fire on protesters in the city.
“Dozens have been killed or injured,” the London-based Baloch Activists Campaign (BAC) said on its Telegram channel. AFP was unable to confirm the toll.
BAC shared a video showing a group carrying a man who appeared to be wounded out of what it said was Zahedan's Makki mosque, Iran's largest Sunni house of worship.
Demonstrators also took to the streets of the Sistan-Baluchistan cities of Iranshahr, Khash and Saravan, said BAC and the 1500tasvir social media monitor.
Oslo-based group Iran Human Rights (IHR) said the Islamic Revolutionary Guard Corps had used military equipment, including heavy machineguns, to suppress the people.
The Kurdish-populated provinces of western and north-western Iran have been hubs of protest since the death of Ms Amini after her arrest in Tehran for an alleged breach of the country's strict dress code for women.
On Tuesday, IHR said Iranian security forces had killed at least 416, including 51 children and 27 women, since the protests began.
Its toll included at least 126 killed in Sistan-Baluchistan and 48 in Kurdistan province. More than 90 were killed during a mass shooting in Zahedan on September 30.
Friday's protests came a day after the United Nations Human Rights Council voted to create a high-level investigation into Iran's bloody crackdown.
Iran condemned the move, saying it was “useless and represents a violation of the country's national sovereignty”.
Agencies contributed to this report