RANCHI: A 20-year-old former undertrial inmate of Birsa Munda Central Jail was allegedly sexually assaulted on three occasions while lodged in the prison, according to a complaint filed by his father.Police registered an FIR on Thursday evening, following intervention by the Ranchi District Legal Services Authority (DLSA).The FIR names 19 people, including several inmates accused of direct involvement in the alleged assaults and jail officials accused of conspiracy and dereliction of duty. The accused include the jail superintendent, a ward in-charge and a medical officer, according to reports based on the FIR.DSP (Sadar) Sanjeev Besra said the case had been filed under relevant provisions of BNS. He said the allegations were being investigated.According to the father’s complaint, the alleged assaults took place during Shivratri, Ram Navami and Sarhul. He alleged that the accused forced his son to wear a saree and declared him “Parvati” during Shivratri. The group allegedly made him consume liquor, following which he became unconscious and was sexually assaulted, the complaint said.The father further alleged that on Ram Navami, the same group again made his son wear a saree and called him “Sita” before assaulting him. He claimed that a similar incident took place during Sarhul festival.The complainant’s son was acquitted by a Ranchi court on June 12. The complaint further alleges that he sought help inside the jail but that his written complaint was allegedly destroyed. It also alleges that he was denied medical treatment for injuries sustained during the assaults.After his release, he reportedly underwent treatment at the Central Institute of Psychiatry in Ranchi.In a statement issued on Friday, DLSA said the survivor had approached them after police allegedly failed to register his complaint. The authority said it forwarded his application to the police and senior officers, following which the FIR was registered.DLSA said they counselled the survivor and his family and appointed an advocate to assist them. It has also sought compensation for him.IG (prisons) Sudarshan Prasad Mandal said the matter was under investigation. Jail superintendent Chandrashekhar denied being informed of the alleged assaults, saying the survivor had not raised the issue with him or officers who visited the prison.