Tehran: A slew of protests erupted in Iran on Tuesday where three people have been killed during the unrest over the death of Mahsa Amini, a 22-year-old woman, following her detention by the country's morality police, a media report said.

Al Jazeera reported that an Iranian Governor, Esmail Zarei Kousha confirmed the news and said that three people died "suspiciously" during "illegal protests" in recent days.

"Investigations have shown that these people were shot and killed by those working against the establishment and with firearms that are not employed by any tiers of security or law enforcement forces in the province," Governor Kousha of the north-western Kurdistan province said.

According to the governor, one person died in Divandareh, another was left in a car near a hospital in Saqqez, and a third "suspicious" death is being investigated.

He further said that families must be careful as "anti-revolutionary" groups wish to use Mahsa Amini's name as a weapon to advance their own purpose.

As per Al Jazeera, Mahsa Amini, 22, was visiting Tehran with her family when the specialist police unit detained her. After a while, she suffered a heart attack and was immediately taken to hospital with the cooperation of the emergency services.

"Unfortunately, she died and her body was transferred to the medical examiner's office," state television said on Friday, reported Al Jazeera. The announcement came a day after Tehran police confirmed Amini had been detained with other women for "instruction" about the rules.

Since Amini's death, several protests have erupted in the country.

They began in her hometown of Saqqez, where she was buried, and spread to several cities in Kurdistan. Women were seen burning hijabs and chopping their hair to mark the protest over the death of Amini.

Iran President Ebrahim Raisi, who called Amini's father earlier this week to promise an investigation is being carried out, left Tehran for New York on Monday to participate in the United Nations General Assembly.

The UN on Tuesday demanded an independent investigation into Amini's death, reported Al Jazeera.

Amini's death comes amid growing controversy inside and outside Iran over the conduct of the morality police, known formally as the Gasht-e Ershad (Guidance Patrol). The mandatory dress code, which applies to all nationalities and religions, not just Iranian Muslims, requires women to conceal their hair and neck with a headscarf, reported Al Jazeera.

Over the decades, women have increasingly pushed back, particularly in the big cities, wearing their headscarves far back on their heads to reveal their hair.