The CBI on Friday took over the ambulance scam in which former Rajasthan Chief Minister Ashok Gehlot, Congress leader Sachin Pilot, Karti Chidambram (son of former Union Minister P Chidambaram) and Ravi Krishna (son of former Union Minister Vayalar Ravi) are accused. The agency re-registered the case earlier filed by the Rajasthan Police following a request from the State Government. Rajasthan Police’s FIR, filed in June last year immediately after the BJP returned to power in the State, has named Gehlot, Pilot, Krishna and Karti Chidmabaram — directors in the private firm Ziquitza.