Four men in Madhya Pradesh allegedly raped a constable in June, but the case came to light only in September after the woman filed a complaint against them, the Hindustan Times reported on Saturday.

The crime took place in a town in Neemuch district, where the 28-year-old woman had gone to attend a birthday party that a friend had invited her to.

The friend and three others allegedly raped the woman at the party, the district’s Superintendent of Police Suraj Kumar Verma told the newspaper. “They also shot a video of the incident and threatened her with dire consequences,” he added.

The woman told her friend’s mother about the incident and she tried to extort money from her, the police said. Another relative of the accused persons also threatened the constable.

The woman said she did not file a rape complaint earlier because she feared social stigma and was being threatened by the accused persons, the newspaper reported. “But when the matter went out of control, due to regular mental torture and threats, I decided to file the case,” she added.

She finally approached the police on September 13. Based on her complaint, the police filed a case against the four men and the mother of her friend. The woman’s friend and his mother have been arrested.

The three other accused persons have fled and efforts are under way to arrest them, India Today reported.