Police probing the April 24 rape and murder of a 9-year-old girl in Madhya Pradesh's Rewa, have found that her teenage brother sexually assaulted her after watching a pornographic video on mobile and then killed her, following which his mother and his two elder sisters helped in the cover-up, an official said.

The police cracked the case and detained the victim's 13-year-old brother, their mother and sisters aged 17 and 18 after interrogation of 50 people, intense questioning of the accused persons and on the basis of technical evidence, he said on Saturday.

Providing details of the case, Superintendent of Police Vivek Singh said, "A nine-year-old girl was raped and strangulated to death under Jawa police station limits on April 24, following which the police had registered a case and started a probe." "The body of the victim was recovered from the courtyard of her house where she was sleeping at the time of the incident," he said.

After the intense interrogation of the family members, it came to light that the victim's 13-year-old brother had slept beside her at night. It was found that the teenage boy raped his sister after watching obscene videos on the mobile phone, he said.

When the victim threatened to tell this to their father, the boy stranguled her and later woke up his mother and confided in his mother. She then found that the victim was still alive. On seeing that, the accused again strangled her, Singh said.

In the meantime, his two elder sisters also woke up and all of them changed the spot of their bed before informing the police to mislead the probe. However, they finally admitted to their crime after being repeatedly interrogated, he said.

Further legal steps are being taken after detaining the boy, his two sisters and their mother, the official said.

"The police received information on April 24 morning that the body of the girl was lying in the courtyard of the house. Evidence relating to rape and murder were found in the post-mortem report and an SIT team was constituted for the probe," Singh said.

In order to mislead the investigators, the family members had told the police that the girl died after being bitten by a poisonous insect, he said.

The probe revealed that there was no sign of anybody entering the house, and family members also denied hearing any sound during the night, he said.

"After collecting technical evidence and interrogation of 50 people, police found repeated changes in the statements of the family members. On the basis of suspicion, they were intensely interrogated, following which they admitted the crime," the SP said.

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