Till six months ago, the CBI could only guess that Kausar Bi, wife of Sohrabuddin Sheikh who had been killed in a fake encounter in 2005 in Gujarat, had also been killed.
But the investigators had no idea about how she was killed or what happened to her body.
To prove the murder, the bureau, however, had to find the body as it held the clues to trace the murderer.
In Kausar's case, since the body had also been destroyed, it became important to find the murder spot and reconstruct the manner in which the body was disposed of.
All that the witnesses told the investigators was that a few days after Sheikh's killing on November 26, 2005, Kausar had been strangled to death and her body was taken from Rajesh Jirawalas's Arham Farms on the outskirts of Ahmedabad to Illol village, about 200 km away.
Although the CBI arrested Jirawala, a BJP corporator, on Tuesday for his role in the case, the bureau had a major roadblock to clear: Where and how in Illol was Kausar's body disposed of?
The investigators found out that one of the prime accused in Sheikh's killing, suspended DIG of police D G Vanzara, owned a farm in Illol.
The investigators sought the help of local Rabaris (cattle breeders), but none of them agreed to help.
"There was no information on how and exactly where Kausar's body was disposed of," said a police officer.
The first breakthrough came as a Rabari of a neighbouring village told the local police that Kausar had been cremated on the banks of a river 1.75 km from the village.
Investigators, disguised as Rabaris, visited the village in March-end and found the spot and carried out detailed probes in April.