CBI had already decided not to file a charge sheet against the five persons arrested by Uttar Pradesh police --Pappu, Awadhesh and Urvesh Yadav (all three brothers) and constables Chhatrapal Yadav and Sarvesh Yadav-- in connection with alleged gangrape and murder of the two teenagers in Katra village.
Agency sources said today that they did not find evidence that the girls had been murdered or were sexually assaulted before their death.
The agency is likely to file its final report tomorrow in Badaun court.
"The Medical Board has come to conclusion that sexual assault on either of the victims appears doubtful," a senior CBI official had said.
The CBI had taken help of the Hyderabad-based Centre for DNA Fingerprinting and Diagnostics (CDFD) which ruled out sexual assault on the two girls.
There was also conflicting statements by the parents of the two cousins.
The sources said the CDFD report had cleared a lot of doubts raised over the cousins being sexually assaulted before being killed.
The five persons had cleared the lie-detection test.
The two cousin sisters--aged 14 and 15--were found hanging from a tree in Badaun district in UP in the last week of May. The incident sparked national outrage with the Samajwadi Party government in the state coming under fire on the issue of law and order situation.
The CBI took over the investigation in June.