Without revealing the findings, CBI sources said the report is a crucial evidence for the investigating team and the case may be cracked anytime now.
The sources said that report of the three-member medical board headed by AIIMS forensic expert is still awaited and they have been asked to expedite the matter.
The panel could not exhume bodies of the two teenaged victims for autopsy because of an apparently delayed decision in this regard. The heavy rains resulted in waters of river Ganga inundating the graves and making it impossible to dig out the bodies for forensic examination.
The clearing of lie-detection test by the accused has put the needle of suspicion on the family. This suspicion grew strong as family members and an eyewitness failed the test.
The sources said the agency is now looking at the role of a local politician who allegedly influenced the family to put blame of the killing on the five accused-- Pappu, Awadhesh and Urvesh Yadav (brothers) and constables Chhatrapal Yadav and Sarvesh Yadav-- who all belonged to a particular caste.