This is the horrifying moment a woman in Iran is dragged off the street by the country's fierce 'morality police'.

In the clip, the woman can be seen grappling with an officer on the street in one of Tehran's student areas.

As the pair struggle, other police officers rush to assist their colleague, who is wearing a traditional hijab, before hauling the student off the street.

They shove her into the back of their unmarked car as she screams out for help from passers-by.

The person who shot the harrowing footage late said: 'I'm a student on Amir Kabir University. This street is close to our university. The area itself is popular hangout place between girls and boys to socialise and to smoke.

'On my way back from university, I realised that the morality police was dealing heavy-handedly with boys and girls.

'When ordinary passers-by were drawing closer to the car of these policemen and policewomen, they faced threats of arrest and were told to mind their own business.'

The woman, who is dressed in black, can be seen grappling with a female officer in a hijab

Other police officers show up to offer backup to their colleague as they try to detain the student (right)

Eventually she can be seen being manhandled into the back of an unmarked car as she screams out for help

This is by no means the only case of brutal treatment by Iran's so-called 'morality police officers' however.

A young woman was recently assaulted by a gang of female police officers who deemed her headscarf 'insufficient' because it only loosely covered her hair.

Terrifying video showing her being savagely beaten was broadcast widely on social media - provoking an outpouring of public sympathy.

In response to the violent attack, a brave woman posed next to a police car without her hijab while a whole family removed their headscarves in solidarity.

A growing number of Iranian woman have taken to the streets without the mandatory hijab in recent days after the video surfaced.

The video has reignited a public debate on the decades-long requirement for women in the Islamic Republic to wear hijabs.

Officials of all ranks up to President Hassan Rouhani have weighed in on the incident as women question being forced to wear the hijab in public.

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

It shows a young woman with a long red scarf loosely covering her head, her hair clearly showing, being surrounded by three morality policewomen wearing chadors, who grab her

On Tuesday, advocacy group My Stealthy Freedom shared a picture of a young woman leaning against a police car without her hair covered.

'Welcome to the 46th week of #WhiteWednesdays!' the caption said.

My Stealthy Freedom, an online group campaigning against the forced hijab, highlights instances of abuse of women who choose not to wear it.

The group's founder Masih Alinejad launched the social media hashtag White Wednesdays, encouraging women to flout regulations posting pictures and videos of themselves without the hijabs online.

She also shared a clip sent to her from a family who posed with their backs to the camera, but with their hair uncovered.

A brave woman posed next to a police car without her hijab in Iran in solidarity with a woman who was viciously beaten by 'morality police officers'

A group of women uncovered their hair in a video shared on Twitter, during which a a man's voice is heard saying: 'I join my family to say NO to forced hijab'

Another woman filmed herself as she walked through the streets of Karaj with her hair uncovered

'I join my family to say no to forced hijab in the hope of freedom for Iran,' a man's voice is heard saying during the clip.

Another woman filmed herself as she walked through the streets of Karaj with her hair uncovered.

'Today I walked the whole way without the compulsory hijab,' she said in the clip.

'I wanted to say that like many, I'm against compulsory veil too. I want to say no to compulsory veil and I hope there comes a day when all Iranian women can take a walk with no fear or stress and without having to put on a compulsory veil.

My Stealthy Freedom was also the first to upload the video of the young woman who was assaulted.

Videos have been posted showing women bravely defying the country's law by walking through the streets of cities like Tehran and Shiraz without the hijab

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

Alongside the video, the group 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.'

Since then, videos have been posted showing women bravely defying the country's law by walking through the streets of cities like Tehran and Shiraz without the hijab.

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

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

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

It shows a young woman with a long red scarf loosely covering her head, her hair clearly showing, being surrounded by three morality policewomen wearing chadors, who grab her.

One grabs her by the throat. She screams, they pick her up off her feet.

She then ends up on the ground, weeping as another woman comforts her before the officers grab her again.

'Why are you hitting me? You have been destroying us for 30 years,' she is heard shouting at one point.

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 on 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.

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

President Rouhani, a cleric who is considered a moderate within Iran's political system, also criticised 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.'

On Monday, judiciary chief Ayatollah Sadegh Amoli Larijani said he supported the morality police, adding that 'law enforcement should not withdraw a single inch.'

But 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.'

Sahar, a 25-year-old university student, agreed.

'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,' she said. 'This method surely will not work.'

The hijab and chador have long been parts of Persian culture.

They became political symbols in 1936, when Iran's pro-Western ruler Reza Shah Pahlavi banned the garments amid his efforts to rapidly modernise Iran.

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

A cleric in Iran was seen demanding a woman covers her hair in another video posted online

The ban became a source of humiliation for some pious Muslim women in the country.

Even before the 1979 Islamic Revolution, the long, flowing black robes for women known as chadors and the headscarves, or hijabs, were both a political and religious symbol in the Shiite-dominated nation.

'I used to be a person who would always say her prayers and deeply believed in God,' said Afrouz, 28, who like other women who spoke to the Associated Press in Tehran would only give their first name for fear of retribution.

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

As the 1979 Islamic Revolution took hold, Ayatollah Ruhollah Khomeini ordered female civil servants to wear the chador.

At first, thousands of women protested the decision in Tehran and Khomeini later said officials should not insult women who chose not to wear it - though he also called the chador 'the flag of the revolution.'

The hijab and loose-fitting clothing later became mandatory for all women in Iran.

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

And though some freedoms for women were curtailed in the years that followed, Iranian women were still allowed to drive, unlike in Saudi Arabia, and hold public office.

A man is seen standing over a woman who is walking in public with her hair uncovered in Iran

In Tehran today, some fashionable young women wear tighter clothes with a scarf loosely covering their head, technically meeting the requirements of the law while drawing the ire of conservatives.

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.

In December, Tehran's police said they would no longer arrest women for not observing the Islamic dress code as video clips of women choosing not to wear hijabs and walking the streets with their heads uncovered spread across social media.

One image - of a young woman, head uncovered and waving her hijab like a flag in Tehran's Enghelab Street - became famous during economic protests that swept Iran later that month.

Tehran's prosecutor, Abbas Jafari Dolatabadi, said in March that the woman had been sentenced to 24 months in prison.

The telecommunication junction box she stood on in the photograph has since been re-welded to stop women from standing on it, though protests continue.