A groundswell of student protests have erupted in India’s southern state of Tamil Nadu after videos showing sexual assaults on college girls were posted on the internet.

Outrage increased after police said the footage was part of plot by an alleged sex blackmail gang.

They said the group of men were using the videos to try to befriend college students on social media, meet them to commit sexual assaults, then use video footage to blackmail them for money.

“Watching the video of a girl begging her assailants to let her go was chilling,” said Captain Prabhakar, a 21-year-old graduate student, who took part in a protest in the city of Coimbatore.

“In many of these areas, girls stepping out of their homes to attend college is a big deal. We fear that cases like this will result in restrictions being imposed again on girls.”

According to government data, the number of crimes against women reported to police in India rose by 83 per cent from 2007 to 2016. Four rape complaints were reported every hour in 2016, the data showed.

20 best pictures of India celebrations following gay sex court ruling Show all 20 1 /20 20 best pictures of India celebrations following gay sex court ruling 20 best pictures of India celebrations following gay sex court ruling Someone celebrates underneath a rainbow-coloured flag as the Supreme Court in India rules that gay sex is longer a crime. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling People celebrate in the street following the ruling. The Chief Justice of India stated that the outlawing of gay sex had been "irrational, arbitrary and indefensible". AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling Up until now, gay sex in India had been punishable by up to 10 years in prison under Section 377 of the Indian constitution. AFP/Getty 20 best pictures of India celebrations following gay sex court ruling The law was originally imposed during the Victorian era while India was still under the rule of the British Empire. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling "Any consensual sexual relationship between two consenting adults - homosexuals, heterosexuals or lesbians - cannot be said to be unconstitutional," said Dipak Misra, Chief Justice of India. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling Members and supporters of the LGBT+ community in India were overjoyed by the decision, with the celebrations awash with rainbow-coloured paraphernalia. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling "They have opened the door to discussing rights," Anjali Gopalan, founder of the Naz Foundation charity that has been fighting against Section 377 told The Independent. "They have apologised to the gay community, and they have said copies of the judgement will be handed to every police station. It is the best judgement we could have hoped for." AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling People were dancing and smiling as the Supreme Court's ruling was announced. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling Bismaya, an activist with the Delhi brand of LGBT+ advocacy group Impulse, told The Independent: "I'm so happy, it's overwhelming. I cried when we heard the news. I'm gay and I'm not afraid of that. It's something I used to say, but now for the first time I have the legal backing." AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling The rain did little to dampen people's spirits as they celebrated the historic ruling in New Delhi. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling A woman exclaims with joy as she holds hands with others on the day of the ruling. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling Members of the LGBT+ community in India hold a placard reading "Love is genderless" while standing outside the Supreme Court in New Delhi. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling The celebrations in India were bright, colourful and full of happiness. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling Bismaya, activist for LGBT+ advocacy group Impulse, said: "It's great for me but it's also a great day for the whole of India. Acceptance in wider society will take time, because we cannot expect change overnight. It has been a battle for two decades for this judgement. If now we get full acceptance in a couple of years, that would be great." AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling Members and supporters of the LGBT+ community in member celebrate the landmark ruling in Siliguri with a cake and confetti. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling People join in the jubilant festivities in Kolkata. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling A woman cries with happiness in Chennai as the ruling made by the Supreme Court in India is announced. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling The celebrations in Kolkata were full of happiness and energy. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling A group of people stand in heavy rainfall in New Delhi as they celebrate the outlawing of the outdated ban on gay sex in India. AFP/Getty Images 20 best pictures of India celebrations following gay sex court ruling The movement to reconsider Section 377 started in 2001 with a legal challenge made to the Delhi High Court from the Naz Foundation. AFP/Getty Images

On Wednesday, police said they arrested four men in the town of Pollachi after a 19-year-old woman lodged a complaint against them.

The woman told police she was sexually assaulted by a group of men inside a car, one of whom she knew. She said the men trapped her, removed her top and filmed her.

The accused men allegedly warned her they would release the video if she did not cooperate with them.

She said they then stole her £220 gold necklace.

Police are now trying to identify other victims based on video footage recovered from the mobile phones of the four accused men. At least five sexual assault videos have been posted on social media.

The teen only gathered the courage to tell her family what had happened almost two weeks later, after the men had repeatedly attempted to extort money from her.

It has been claimed this attack was just one in a series committed by the gang, with local media suggesting they have been targeting women since 2013.

Student protesters and women’s rights campaigners called for police to quickly investigate the assaults and provide protection for the victims, many of whom have since been identified through the videos.

Naam Tamilar Katchi, a Tamil nationalist party, staged a demonstration rebuking alleged inaction by the police.

And campaigners have warned that victims of the alleged sex blackmail gang may not come forward after the name of a victim was made public by government officials.

The woman’s name was contained in an official document published by the Tamil Nadu government. It is illegal in India to report the name of a sexual assault victim.

Violence against women is a widespread problem in India – more than 50 per cent of Indian men and women still believe that wife-beating can be justified.

One woman is killed every hour for not providing enough dowry, according to 2013 statistics. A dowry is an amount of property or money given by a bride to her husband at the time of marriage.

But the conviction rate for crimes against women in India is very low – only 18.9 per cent and the lowest in a decade – according to the latest official crime statistics from 2016. The average conviction rate for all crimes is 47 per cent.

Rape is one of the most under-reported crimes in India – with some estimates indicating 90 to 95 per cent of rape cases remain unreported.

Sexual violence continues to be a taboo in the subcontinent and survivors are fearful of stigma or retribution if they report attacks.

However, the number of cases police register has been steadily rising following national outrage at the fatal gang rape of a student on a bus in New Delhi in 2012.

“The need of the hour is to help other victims break their silence and come forward with their complaints,” said Henri Tiphagne, director of human rights’ charity People’s Watch.

“We need to create a safe atmosphere for the other victims,” said Mr Tiphagne, who is based in Madurai, one of the major cities in Tamil Nadu.

The National Commission for Women, a statutory body that advises the Indian government, sent a letter to police saying they were “seriously concerned about the safety and security of women in Tamil Nadu”.