The death of 22-year-old Mahsa Amini following her arrest and alleged assault by Iran's notorious morality police almost three months ago sparked the biggest protests in the Islamic republic in years.

Women and girls have led the charge against compulsory headscarves.

A general in Iran's Islamic Revolutionary Guard Corps has said more than 300 people, including security force members, lost their lives in the protests.

The Oslo-based Iran Human Rights group gives a toll of at least 448 people "killed by security forces".

Here is a timeline of the events:

- Sept. 13: Amini's arrest -
 

Amini is visiting Tehran with her family when she is detained by the Gasht-e Ershad (Guidance Patrol), the police unit that enforces strict dress rules for women, including the mandatory hijab or headscarf.

She is rushed to hospital later that day. Police claim she "suddenly suffered a heart problem". CCTV footage from the police station appears to show her collapsing.

- Sept. 16: death -
 

After three days in a coma, Amini is declared dead.

Rights activists say she suffered a fatal blow to the head while in custody, a claim echoed by a relative of Amini living in Iraq, but denied by officials.

President Ebrahim Raisi orders an inquiry.

- Sept. 17: first protests -
 

Amini is buried in her hometown of Saqez in Kurdistan province of northwest Iran. Police use tear gas after some residents demonstrate.

In the following days, the hashtag #Masha_Amini clocks up more than one million tweets, including many videos of Iranian women cutting their hair to protest her death.

Demonstrations break out at several universities in Tehran.

- Sept. 20: first deaths -
 

Three people are reported killed during protests in Kurdistan province.

Videos posted on social media show women removing their veils and chanting "Woman, life, freedom" or "Death to the dictator", a slogan directed at Ayatollah Ali Khamenei, Iran's supreme leader.

- Sept. 22: social media muzzled -
 

Iran blocks access to Instagram and WhatsApp, the two platforms most widely used in Iran. It imposes drastic restrictions on internet access.

The US places the morality police on its sanctions blacklist.

- Sept. 23: counter-demonstrations -
 

Thousands take part in pro-hijab counter-demonstrations in Tehran and other cities, in response to a call from the authorities.

On September 25, Raisi vows "decisive action" to end the anti-hijab protests. A day later, more than 1,200 protesters are arrested.

- Oct. 3: Khamenei accuses US -
 

Khamenei accuses arch-foes the United States and Israel of fomenting the unrest.

- Oct. 8: death by illness -
 

An official medical report concludes Amini's death was caused by illness, due to "surgery for a brain tumour at the age of eight", and not police brutality.

Activists hack a state television live news broadcast, superimposing crosshairs and flames over an image of Khamenei.

- Oct. 15: prison blaze -
 

A fire erupts during clashes at Tehran's notorious Evin prison, where hundreds of those detained during the demonstrations are being held.

The blaze kills eight inmates, according to authorities.

- Oct. 26: mass rally in Amini's hometown -
 

Crowds pour into Amini's hometown to pay tribute at her grave to mark the end of the traditional 40-day period of mourning.

As protests break out, Iranian security forces open fire on the crowd.

- Nov. 13: first death sentence -
 

A Tehran court hands down the first death sentence over the protests to a demonstrator accused of "corruption on earth", one of the most serious categories of crimes in Iranian law.

- Nov. 15: strike -
 

Protesters hold strikes and demonstrations to mark three years since a deadly crackdown on unrest sparked by a fuel price hike in 2019 -- the last time Iranians took to the streets in large numbers.

- Dec. 4: morality police scrapped
 

"Morality police have nothing to do with the judiciary and have been abolished," Attorney General Mohammad Jafar Montazeri is quoted as saying by the ISNA news agency.