Dozens of women have taken to the streets of Iran without the mandatory hijab, after a video emerged showing 'morality police officers' brutally beating a young woman whose veil they deemed 'insufficient'.

Videos show them bravely defying the country's Islamic law, which requires women to cover their hair in public, as they walk through cities like the capital Tehran and Shiraz.

Several of them face verbal and physical abuse in the street, with witnesses urging them to cover their hair.

Protest: One of the many brave Iranian women who has taken to the streets in the wake of the horrific abuse by morality police seen in a video last week gets asked why she is not veiled

Their protest has been named #WalkingUnveiled, and is quickly spreading on social media.

Their campaign is a response to the vicious assault last week, which has sparked a new public debate on the decades-long requirement for Iranian women.

The video appeared online last week, with activists suggesting it was taken in Tehran, though nothing in it offers hints at its location.

The outrageous scene, in what appears to be a public park in broad daylight, was secretly filmed by an onlooker and has been spread online by dissident groups.

The disturbing footage initially shows a woman with a red scarf pushed to the back of her head having a heated conversation with a man and another woman.

Seconds later, two women wearing all-black coverings that leave only their faces visible barge onto the scene and begin grabbing and shouting at the woman.

Videos show women bravely defying the country's Islamic law, which requires them to cover their hair in public, as part of the #WalkingUnveiled protest

Abuse: A man is seen standing over a woman who has exposed her heir in public in Iran

The aggressive women - who are believed to be members of the Islamic theocracy's morality police - become increasingly violent towards their frightened victim.

Other women, who do not appear to be members of the force, assist the primary attackers as an argument rages throughout.

The victim can be heard screaming in terror, and can later be seen lying on the floor, crying in pain and without her head scarf, as a large crowd surrounds her.

At the end of the video, the brutal attackers can be seen pointing and shouting at members of the crowd who appear to disagree with their barbaric actions.

The video went viral on social media and drew an immediate reaction from officials of all ranks up to President Hassan Rouhani.

President Rouhani, a cleric who is considered a moderate within Iran's political system, also criticized the morality police in a speech on Saturday. The police force's stated mandate is 'promoting virtue and preventing vice.'

'Grabbing people's collars to promote virtue will not work,' Rouhani warned. 'You cannot do it by being aggressive.'

Attack: A cleric is seen demanding that a woman covers her hair in another video

No bother: One of the women documented a completely harassment free shopping trip, and posted the video of herself walking down a street without any issues

Iran's interior minister, Abdolreza Rahmani Fazli, ordered authorities on Thursday to investigate the incident soon after Masoumeh Ebtekar, a female vice president for women's affairs, condemned the police's 'violent' approach to the situation.

Reformist lawmaker Tayebeh Siavoshi said Saturday that the policewoman seen in the video grabbing the young woman's throat has been suspended pending the investigation. None of the women in the video have been identified.

'Imposing (force on women) will lead nowhere,' she said.

On the streets of Tehran, women are openly discussing the video and their own encounters with morality police.

'I think that it was very unnecessary the way that the police, or the morality police, handled the situation,' said Hamraz, 27, an Austrian national born to Iranian parents who is on vacation in Tehran.

'It was very unfortunate that it was caught on camera, but in a way it was good that everyone got to see how people are being treated: very unjust and very unfair.'

The aggressive goons - who are believed to be members of the Islamic theocracy's morality police - become increasingly violent towards their frightened victim

The victim can be heard screeching in terror as the sickening abuse continues. At the end of the video, the brutal attackers can be seen pointing and shouting at members of the crowd who appear to disagree with their barbaric actions

The veil has been a mandatory dress requirement for women in Iran since the Islamic Revolution in 1979. Pictured: The terrified victim is beaten by the thugs

Sahar, a 25-year-old university student, agreed, saying: 'I think everyone must be free to choose what they believe in and we can deal with each other more peacefully instead of trying to induce people to do what you think is right. This method surely will not work.'

Afrouz, 28, who also only gave her first name for fear of retribution said: 'I used to be a person who would always say her prayers and deeply believed in God.

'I would always say grace before having a meal. Right now, I believe in none of those things.'

My Stealthy Freedom, an online group campaigning against forced hijab and highlights instances of abuse of women who choose not to wear them, were the first to upload the video.

In a description of the footage, the activists wrote: 'This woman is savagely beaten up by morality police as punishment for her insufficient hijab. And they tell us hijab is a 'small issue'.'

They added: 'We expose them and we resist compulsory hijab.'

The group's founder - and also the founder of the anti-hijab 'White Wednesdays' movement - said to the thugs who beat the woman: 'Shame on you'.

She can later be seen lying on the floor, crying in pain and without her head scarf, as a large crowd surrounds her

The disturbing footage initially shows a woman with a red scarf pushed to the back of her head having a heated conversation with a man and another woman

White Wednesdays encourages women to flout regulations by capturing footage and pictures of themselves without their hijabs and posting it online.

The veil has been a mandatory dress requirement for women in Iran since the Islamic Revolution in 1979.

The Islamic code also forbids women touching, dancing or singing with men outside their families.

Women are only allowed to show their face, hands and feet in public and are supposed to wear only modest colours.

Women arrested for showing their hair in public in Iran can receive jail terms of two months or less and face fines equivalent to $25.

Over the years, however, women have pushed back the boundaries of the law, with many wearing loose, brightly coloured headscarves far back on their heads.

The My Stealthy Freedom and White Wednesdays movements have also grown in recent months, following several well-publicized arrests of women who have removed their hijabs in public.