MUMBAI: Police in Mumbai have arrested three officers who allegedly raped a model in a police station and then demanded Rs500,000 as blackmail to keep quiet, a deputy commissioner said Friday.

Three other men have also been arrested after the 29-year-old woman said the officers bundled her into a car as she was leaving an upmarket hotel in India's financial capital on April 3.

According to Deputy Commissioner Dhananjay Kulkarni the woman said she was then driven to a police outpost and raped by the officers before they extorted up to Indian Rs500,000 from her.

“The investigations are being done meticulously considering the involvement of police and nature of the crime,” Kulkarni said.

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“Right now, the allegations of extortion seem genuine, but the matter of sexual assault cannot be confirmed at this moment."

“They [the policemen] had no business to be there” outside the hotel, he also said.

Indian media have reported that the woman's friend had gone to the police station to deliver the money after travelling to several Automated Teller Machines (ATMs) in the night.

The woman reportedly sent a text message to Mumbai's police commissioner Rakesh Maria several days later alerting him to the incident, before meeting him to give more details.

India introduced tough laws against sex offenders in the wake of the fatal gang-rape of a Delhi student in the capital in December 2012 that sparked mass street protests, jolting many in the world's second most populous country out of apathy, and forcing the government to enact stiffer penalties on gender crimes.

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But sexual violence against women has continued at frightening levels throughout the country.

Voracious reporting by the media, campaigns by the government and programmes by civil society groups have brought greater public awareness of women's rights and emboldened more victims to come forward and register abuses.

In 2013 Indian authorities received 309,546 reports of crimes against women, a 26.7 per cent jump from 2012, according to the National Crime Records Bureau.

But in many small towns and villages, most cases still go unreported due to the shame and stigma attached to rape in these conservative societies, where the victim is often blamed.

In some villages, local councils act as de facto courts, often ordering rape to punish women.

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