The Delhi Police has approached the Central Bureau of Investigation to conduct a psychological autopsy of the 11 members of a family who were found dead at their home in north Delhi’s Burari, officials said on Thursday. Police have asked the Central Forensic Science Laboratory to constitute a panel of psychologists to analyse the psyche of the deceased, reported PTI.

Police said that a psychological autopsy is conducted to study a dead person’s mental state by analysing his/her medical records, conducting interviews with family and friends, and researching their state of mind prior to death.

On July 1, 10 members of the family were found hanging in the living room of their house while the last body, that of 77-year-old Narayan Devi, was found on the floor in another room. The dead included Devi’s two sons, a daughter, a daughter-in-law, and grandchildren. The mouths and eyes of the corpses were covered and their hands tied behind their backs. Investigation showed that it was a case of failed suicide and that the family had not expected to die during a supposed life-improving ritual. While relatives alleged foul play, no signs of forced entry or other evidence was recovered.

Police later found 11 diaries, complete with notes, which indicated that Narayan Devi’s 45-year-old son Lalit may have forced the family to participate in the ritual that led to their deaths.