Police have fired tear gas to disperse a protest rally in western Iran following the funeral ceremony for a young woman who died in police custody in Tehran earlier this week, the semi-official Fars news agency reported.

The police said 22-year-old Mahsa Amini, who was detained on Tuesday after Iran’s so-called “morality police” found fault with her headscarf, or hijab, had died of a heart attack.

The police also released closed-circuit footage from the police station, which they say shows the moment Amini collapsed. A relative has said she had no history of heart disease.

Her body was laid to rest in her hometown of Saghez, 460km (285 miles) from Tehran in northwestern Kurdistan province, on Saturday morning, Fars reported.

“Following the funeral ceremony, some people left the scene while others remained, chanting slogans demanding detailed investigations into the dimensions of the story,” the agency said.

“The protesters then gathered in front of the governor’s office and chanted more slogans but were dispersed when security forces fired tear gas,” it added.

Amini’s death triggered an outcry against the morality police from celebrities and prominent figures on social media. Iran’s judiciary launched an investigation into her death.

Headscarves are compulsory for women in Iran since the 1979 Islamic Revolution, and members of the morality police enforce the strict dress code.

They have been criticised in recent years over their treatment of people, especially young women, and videos uploaded on social media have shown officers forcing women into police vehicles.

Since 2017, after dozens of women publicly took off their headscarves in a wave of protests, authorities have adopted tougher measures.

However, the reformist Etemad Melli political party urged Iran’s parliament to cancel the law on the mandatory hijab and suggested President Ebrahim Raisi do away with the morality police.

The Kasra Hospital in Tehran, where police took Amini after she collapsed and slipped into a coma, said she was brought in without vital signs.

Iranian filmmaker Asghar Farhadi, who rarely reacts publicly to events in Iran, expressed sorrow and called Amini’s death in custody a “crime”.

Iranian ultraconservatives have called for harsh punishment and even lashes for women who disobey the hijab law, arguing that allowing women to show their hair leads to moral decay and the disintegration of families.

The judiciary has in recent years urged people to inform about women who do not wear the hijab.