Iranians based abroad and their supporters gathered in cities around the world Saturday in solidarity with protests sparked by the death of Mahsa Amini in the custody of the country's notorious morality police.

A wave of street violence has rocked Iran since Amini, 22, died days after her arrest by the morality police for allegedly failing to observe the Islamic republic's strict dress code for women.

Protests were held across Iran for a 15th consecutive night on Friday, despite a bloody crackdown that a rights group says has claimed more than 80 lives.

"Woman, life, freedom" and "Death to the dictator", they chanted in the streets of Amini's hometown of Saqqez, in Kurdistan province.

Riot police massed Saturday at major intersections in Tehran, amid reports of demonstrations at universities to seek the release of arrested students.

The 1500tasvir social media channel shared video footage of large demonstrations in the capital, as well as the shrine city of Mashhad and Kermanshah in the west.

Demonstrations in support of the movement are being held meanwhile in 159 cities across the globe -- from Auckland to New York and Seoul to Zurich, according to the Iranians for Justice and Human Rights group.

"Be our voice," was the catchcry of a protest in the eastern Australian city of Brisbane, where organisers said thousands from the Iranian diaspora demanded freedoms in their homeland.

In Tokyo, demonstrators waved pictures of Amini and other women who defiantly burned their headscarves and cut their hair during the Iranian protests.

Arrest of foreigners

The protests flared in Iran on September 16, when Amini was pronounced dead three days after falling into a coma following her arrest.

Oslo-based Iran Human Rights group says at least 83 people have been killed in the crackdown. Amnesty International says it has confirmed 52 fatalities, while Iran's Fars news agency has put the death count at "around 60".

It is the bloodiest unrest in Iran since a ruthless crackdown on demonstrations in November 2019 over a sudden hike in fuel prices which killed at least 304 people, according to Amnesty.

Security forces used live ammunition and tear gas on Friday to try to disperse demonstrations in various cities and towns across the country.

Iran's intelligence ministry said "nine foreign nationals", including from France, Germany, Italy, the Netherlands and Poland, were arrested "at or behind the scene of riots", along with 256 members of outlawed opposition groups.

Unrest also erupted on Friday in Iran's southeastern Sistan-Baluchestan province, which borders Afghanistan and Pakistan.

The Islamic Revolutionary Guard Corps said two of its colonels were killed, bringing the overall toll to 20 dead during the clashes in which three police stations were attacked.

Outside forces

"Several chain stores were looted and set on fire, and a number of banks and government centres were also damaged," said Sistan-Baluchestan governor Hossein Khiabani.

Poverty-stricken Sistan-Baluchestan is a flashpoint for clashes with drug smuggling gangs, as well as rebels from the Baluchi minority and Sunni Muslim extremist groups.

Iran has blamed outside forces for the nationwide protests.

On Wednesday, the Revolutionary Guards launched cross-border missile and drone strikes that killed 14 people in autonomous Iraqi Kurdistan, accusing rebel groups in the region of fuelling the unrest.

The US said one of its citizens was killed in the strikes.

Amnesty said Iran was intentionally using lethal force to crush the women-led protests.

It said it had obtained a leaked document issued to armed forces commanders in all provinces on September 21 ordering them to "severely confront" protesters.

Another leaked document showed the commander in Mazandaran province told forces to "confront mercilessly, going as far as causing deaths, any unrest by rioters and anti-revolutionaries".

Fifty-four countries signed a statement "urging Iran to stop using force against peaceful protesters", the US special envoy for Iran, Robert Malley, tweeted.

The warning comes as Iran presses ahead with an intensifying crackdown that has seen the arrest of many journalists, activists and other prominent figures.