CBI sources said the fathers of the rape victims, a family member and a witness have been brought to undergo polygraph test at Central Forensic Science Laboratory in CGO complex here.
Protesting the move, the victims' brother Virendra along with the members of Naya Daur Party sat on fast unto death here at Jantar Mantar alleging that CBI is harassing his family by subjecting his father to lie-detector test.
The sources said they have taken three-days time from the court in Badaun to subject these four persons to polygraph or lie-detector test but if the procedure is completed earlier they may be allowed to go.
They said during the test which started today, the family members of the victims were repeatedly asked about the mobile phone of the girls and why it was broken.
The CBI sources said they are not doubting the claims made by the families of the victims but in order to develop a flawless case the agency needs to test the veracity of their statements.