Protests raged through the night in Iran after thousands of mourners marked 40 days since the death of Mahsa Amini which sparked a wave of unrest across the Islamic republic.
Amini, a 22-year-old Iranian of Kurdish origin, died on September 16, three days after her arrest in Tehran by the notorious morality police for allegedly breaching the Islamic dress code for women.
Anger flared at her funeral last month and quickly sparked protests led by young women who have burned their headscarves and confronted security forces, in the biggest wave of unrest in Iran for years.
More than five weeks after Amini's death, the demonstrations show no signs of ending, fuelled by public outrage over a crackdown that has claimed the lives of other young women and girls.
Despite heightened security measures, columns of mourners had poured into Saqez on Wednesday, paying tribute to Amini at her grave at the end of the traditional mourning period.
In a virally-shared picture verified by AFP, a young woman was seen standing on the roof of a car without a hijab head covering, looking into the distance at the highway packed with scores of vehicles and people.
Mourners chanted at the Aichi cemetery outside Saqez, before many were seen heading to the governor's office in the city centre, where Iranian media outlets said some were poised to attack an army base.
"Security forces have shot tear gas and opened fire on people in Zindan square, Saqez city," the Hengaw rights group said, without specifying whether there were any dead or wounded.
After nightfall, blasts were heard as security forces fired on protesters in Marivan, Kurdistan province, in a video published by Hengaw, a Norway-based organisation.
- Internet cut -
"Death to the dictator," chanted protesters in the nearby city of Bukan where bonfires burned in the streets, the rights group said.
Protesters also surrounded a base of the Basij militia in Sanandaj, a flashpoint city in Kurdistan province, starting fires and driving security forces back, it added.
There were similar scenes in Ilam city, near Iran's western border with Iraq.
Iran's ISNA news agency said the internet had been cut in Saqez for "security reasons", and that nearly 10,000 people had gathered in the city.
But many thousands more were seen making their way in cars, on motorbikes and on foot along a highway, through fields and even across a river, in videos widely shared online.
Noisily clapping, shouting and honking car horns, mourners packed the highway linking Saqez to the cemetery eight kilometres (five miles) away, in images Hengaw said it had verified.
ISNA said some of the crowd returning from the cemetery had "intended to attack an army base", until they were dispersed by other participants.
A police checkpoint was torched and fires burned beside a bridge in the Qavakh neighbourhood of Saqez, according to a verified video.
"This year is the year of blood, Seyed Ali will be toppled," a group of them chanted in footage verified by AFP, referring to Iran's supreme leader Ayatollah Ali Khamenei.
Hengaw said workers went on strike in Saqez as well as Divandarreh, Marivan, Kamyaran and Sanandaj, and in Javanrud and Ravansar in the western province of Kermanshah.
- Fresh sanctions -
Kurdistan governor Esmail Zarei-Kousha accused Iran's foes of being behind the unrest.
"The enemy and its media... are trying to use the 40-day anniversary of Mahsa Amini's death as a pretext to cause new tensions but fortunately the situation in the province is completely stable," he was quoted as saying by state news agency IRNA.
The social media channel 1500tasvir, which chronicles rights violations by Iran's security forces, said fresh protests flared at universities in Tehran, Mashhad in Iran's northeast, and Ahvaz in the southwest, among others.
Oslo-based group Iran Human Rights says the security forces' crackdown on the Amini protests has claimed the lives of at least 141 demonstrators, including at least 29 children.
Amnesty International says the "unrelenting brutal crackdown" has killed at least 23 children.
The United States slapped sanctions on more than a dozen Iranian officials over the bloody response to the protests.
The White House said it was "concerned that Moscow may be advising Iran on best practices to manage protests, drawing on... extensive experience in suppressing" opponents.