Sources say the CBI will start questioning suspects mentioned in the preliminary enquiry of AgustaWestland deal. It is learnt that an FIR will be registered only if CBI gets evidene of bribe in the money trail. Armed with documents from Italy, CBI on Monday (Feb 25) named former Air Force Chief S P Tyagi in its Preliminary Enquiry into allegations of kickbacks in the Rs 3,600 crore VVIP chopper deal, the second former defence services chief to figure in a scam probe. Besides the former IAF chief, 10 others including his cousins--Julie, Docsa and Sandeep Tyagi have also been named along with four companies in the PE, CBI sources said. CBI has registered the PE to probe allegations that some "middlemen have influenced the deal in favour" of the Italian company AgustaWestland for the supply of 12 helicopters.