"The graves are under about seven feet of water and the red flag put up to identify the burial place has been washed away," executive engineer of Badaun's Flood Division D K Jain said here today.
Jain said the water level in the area is expected to rise further and if the sand bags placed around the graves are washed away it would be difficult to identify the place where the bodies of the two sisters, who were allegedly raped and hung by a tree at Katra village on May 28, had been buried.
The CBI, which has taken up investigation into the case, had made an attempt to exhume the bodies for a second autopsy last month, but it had to be stopped due to the rise in the water level.