The woman and the accused had studied together, police said.
A woman was allegedly raped by four men in Mathura, who also made a video of the incident and sent it to her in-laws, police said.
Police said on Saturday that three of the four accused have been arrested in the case.
The survivor had gone to a public service centre on May 28 to fill a form for the post of Anganwadi worker when the operator of the centre, a computer operator, a shop owner and another man sexually assaulted her.
"The matter came to light when one of the accused sent the video to the woman's in-laws," SP (Rural) Shrish Chandra said.
He said the main accused belongs to the same village in Aligarh district where the woman's parents lived. The woman and the accused had also studied together, the officer added.
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