The 21-year-old colleague of the photojournalist who was gang raped at Shakti Mill, Mahalaxmi, on August 22, told the police that he did not know she was being raped until they were finally freed by their attackers. At the time, he said, he believed the rapists' claim that they were cops investigating a murder, and thought his colleague was being interrogated.A 600-page charge sheet was filed at the Esplanade court yesterday, 28 days after the incident. There are total 86 witnesses, 18 panchnamas, eight call data records and 22 DNA reports.The attackers, who had tied up the girl's colleague about 15 feet away - but out of sight - from where they raped her, took turns guarding him while the others assaulted her. Despite her screams, her colleague did not imagine that she was being raped. When he asked his captors what was happening, they simply replied, "Enquiry chalu hai."He told the police in his statement that he realised they were not safe when the accused began leading them deep inside the abandoned mill. When he tried to scream for help, one of the accused, Salim Ansari, punched him in the stomach and warned him to keep quiet.He added, “I was tied and made to sit around 15 feet from the walled structure where [the girl] was taken. After some time I heard her screaming and asked Ansari what was happening, to which he said 'enquiry chalu hai'.“He also said that the attackers did their best to keep up the pretense of an inquiry in their conversations. He said in hi statement, “[Kasim] Bangali at one point told Ansari that since neither of them was revealing any information, something needs to be done about it. He then told Ansari to go inside."It was only when the rapists freed the girl did he realise what had happened. "She was scared and crying continuously. The moment she came close to me she held my hand and began wailing. After they left us on the train tracks, she finally told me what had happened."