CCTV camera footage obtained from South Calcutta Law College has corroborated the gangrape allegations made by a first-year student in her written complaint to police, an investigating officer said on Saturday.

The footage, spanning over seven hours — from 3.30 PM to 10.50 PM on June 25 — captured movements around the college premises, including the victim being forced into the guard's room.

"The CCTV footage confirms the girl's allegations. It shows the movements of the three accused, the security guard, and the victim. We are currently examining the footage," the officer said.

Investigators also collected evidence from three locations on campus — the students’ union room, the washroom, and the guard’s room — that supports the victim's claims.

Seized items include strands of hair, several bottles containing unknown liquids, and a hockey stick.

"There are clear signs of a struggle in all three rooms. The samples have been sent for forensic examination," the officer added.

In her complaint, the victim reported that she was threatened with a hockey stick by the accused.

Investigators also recovered a 1.5-minute video clip from a mobile phone belonging to one of the three arrested suspects — Manojit Mishra (an alumnus and ad-hoc staff), along with current students Pratim Mukherjee and Zaib Ahmed.

"A forensic analysis of the video is underway. We're trying to determine if it was shared or deleted," the officer said.

On Saturday morning, police arrested college security guard Pinaki Banerjee after he failed to provide coherent responses during questioning.

"The guard did nothing to protect the victim. Evidence suggests he left the scene even as the victim was forcibly taken into his room by the main accused, while the other two stood guard outside," the officer told PTI. So far four persons have been arrested in the case.

Kolkata Police has formed a five-member Special Investigation Team (SIT), led by Assistant Commissioner of Police (South Suburban Division), Pradip Ghoshal.

The SIT is expected to record a confidential statement from the victim and her parents.

The victim appeared in a city court on Saturday afternoon to provide her secret deposition.

Discussing a possible motive, the officer said, "We suspect the gangrape occurred after the victim rejected a marriage proposal from Manojit Mishra, which enraged him." Police were also trying to find out whether the entire crime was pre-planned, he said.

"Going by the sequence of events, it appears that the prime accused tortured the victim after she rejected his marriage proposal. This has been corroborated by the circumstantial evidence," the officer said.

"But whether it was a pre-planned crime needs to be proved," the officer told PTI.

According to the investigators, the woman told the three accused that she had a boyfriend and was "happy with him" and would not "cheat him".

The trio then threatened to kill her boyfriend and lodge false cases against her parents if she continued to resist the prime accused's proposal, she alleged.

On Friday, the medical examination had corroborated the law college student's allegation that she was gang raped.

Meanwhile, the National Commission for Women (NCW) on Saturday wrote to West Bengal Chief Secretary Manoj Pant asking him to take action in connection with the crime.

NCW Chairperson Vijaya Rahatkar termed the crime as "grave" which has "shaken public conscience".

"This incident is not just an individual crime; it's a blow to our collective sense of security. It demands a swift and institutional response from the state," she wrote.

She also requested a confidential and comprehensive internal and external medical examination report of the survivor within three days.

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