The Iranian woman who protested the country's 'modesty' dress code by standing on a pillar box in Tehran and waving a hijab, is missing and feared to have been arrested.

She had taken off her white headscarf and tied it to a stick in an apparent reference to the 'White Wednesday' protests against clothing restrictions on women in Iran.

Not covering your hair in public is a punishable offense for Iranian women, and the unnamed protester, a 31-year-old mother-of-one, is believed to have been arrested by police.

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The mystery woman (pictured) was praised after a video of her standing on a pillar box without a headscarf went viral on social media

The woman has not been seen since the video of her standing on the pillar box on one of the city's busiest thoroughfares, without a headscarf or long coat as required under Islamic law, went viral.

The video, widely shared on social media, showed her waving a white scarf in a solemn and brave protest.

The video and images of the woman are thought to have been taken on December 27, a day before economic protests broke out across the country, which helped the images go viral even though they were apparently unconnected.

Thousands of social media users have shared messages, dubbing her the 'Girl of Enghelab Street' after the area in central Tehran where she staged the protest.

In the footage, she could be seen waving a white scarf which appeared to be her own head covering and the brave woman is now missing, having not been since

The Girl of Enghelab Street: What she stood for The woman who took her hijab off in public and waved it like a white flag in central Tehran, was protesting the Islamic dress code enforced on women in Iran. The woman, reportedly a 31-year-old mother, broke the law by exposing her hair in public, risking arrest and fines. The Girl of Enghelab Street, nicknamed so because of the name of the road where she took her head-scarf off in protest, has spurred many other women in Iran to do the same. Missing: The unnamed woman was taking part in a women's movement called White Wednesdays, which protests the enforcing of strict Islamic dress codes in Iran Since her protest on December 27, she has become a symbol for Iranian women's fight against compulsory hijab, with many sharing the video of her protest on social media and illustrations of her brave stand. She has become the 'poster child' for the White Wednesdays movement, which encourages Iranian women and those who support their plight to take off their hijab, and was started by journalist and campaigner Masih Alinejad. White is one of the most common colours of headscarves in Iran, which only allows 'modest' shades such as white, brown or black. Another campaign fighting against the enforced hijab in Iran set up by Ms Alinejad is My Stealthy Freedom. It is 'dedicated to Iranian women inside the country who want to share their “stealthily” taken photos without the veil', and aim to be a 'living archive' of their fight. Movement: Supporters have been sharing graphic illustrations of the Girl of Enghelab Street, painting a picture of her as an iconic fighter for women's rights in Iran It sees women post 'stealth' photos or videos of themselves where they have dared to take off their hijab, to spread the message and protest. Some women film themselves walking down public streets without their headscarf to show to the world the amount of abuse they face if they dare show their hair. Since the 1979 revolution, Iran has required women to wear the Islamic headscarf in public. 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. Leader: The Girl of Enghelab Street is being depicted as Moses in the Bible, parting the Red Sea This image shared on social media shows a person in an unknown location having built a snow statue of the Girl of Enghelab Street Advertisement

Using the hashtag '#Where_is_she?', supporters have been sharing the video and images of the woman, demanding that authorities reveal her whereabouts.

Graphic illustrations show her fighting dragons and using her hijab as a weapon against police batons.

Others have been inspired by her brave protest, and copied her act of defiance by filming themselves waving their headscarf in public.

These include the founder of the My Stealthy Freedom movement, Masih Alinejad, who posted a video showing her walking through traffic and waving her headscarf.

She captioned the video: 'Me alone but strong waving my veil in public, shouting freedom. U arrested the woman who waved a white headscarf in Enghelab Ave but we are all repeating her protest. together on #WhiteWednesdays we shout #Where_is_She [sic]'

Nasrin Sotoudeh, a renowned human rights lawyer, has taken it upon herself to investigate the disappearance, and said she is certain the woman is in custory.

Ms Sotoudeh said she could not find out the woman's name, but had been told she was 31 years of age, and had a 19-month-old baby.

'What I am certain about is that this lady has been arrested,' she told AFP.

'The witnesses on the scene who saw her being taken away and even accompanied her to the police station gave me this information. I have no contact with her family.'

Copycat: Masih Alinejad, the founder of My Stealthy Freedom, is filmed walking through traffic while waving her headscarf

Supporter: The video was filmed at an unknown location Iran, and she is seen having ripped off her hijab and holding it up in defiance

Ms Sotoudeh said the woman's protest appeared to show someone 'at the end of their tether because of all the controls placed on her body over the 31 years of her life'.

'Women feel they have no control over their bodies. It is a prelude to infringing on all of their rights,' she said.

The woman was protesting Iran's Islamic legal code, which requires women to wear a headscarf and long clothes that cover the arms and legs.

Breaking the rules can bring fines of up to 500,000 rials ($12) and up to two months in prison.

On the same day the unnamed woman took to her pillar box on December 27, Tehran's police chief indicated security forces were taking a softer line on Islamic rules.

Brigadier General Hossein Rahimi said that instead of jailing women and giving them a criminal record, they would be forced to undergo 're-education' at so-called counselling centres.

'According to a decision of the commander of the police force, those who do not observe Islamic codes will no longer be taken to detention centres nor judicial files opened on them.

'We offer courses and 7,913 people have been educated in these classes so far.'

Mandatory headscarves for women have been a key symbol of Iran's Islamic rule since the 1979 revolution

However, Rahimi did not elaborate on which Islamic codes were in question or when the new guidelines were introduced, and according to human rights campaigners, not much has change since since his speech.

Ms Sotoudeh even claims that police of frequently go beyond what is punishable by law for not wearing a headscarf.

She said: 'Before even being tried by legal authorities, (women) are taken to a place called 'Gasht-e Ershad' [Guidance Patrol], where they can be harshly beaten up. Whether a case is opened for them or not is not important.

'The illegal punishment they have had to bear has always been much more than what is foreseen in the law.'

President Hassan Rouhani, who came to power in 2013 promising a more moderate stance, has previously said it is not the job of police to enforce religious rules.

But in April 2016, officials said there were 7,000 undercover morality police reporting on things like 'bad hijab' - a blanket term usually referring to un-Islamic dress by women.

Figures are rarely given, but Tehran's traffic police said in late 2015 they had dealt with 40,000 cases of bad hijab in cars, where women often let their headscarves drop around their necks.

These cases generally led to fines and a temporary impounding of the vehicle.