CBI on Wednesday filed an FIR against former IAF Chief S P Tyagi and 12 others for alleged cheating and criminal conspiracy in Rs 3600 crore VVIP Helicopter deal.

Two new names, which were not part of the agency's preliminary enquiry, have also been included in the FIR. They include brother of former Union Minister Santosh Bagrodia, Satish Bagrodia and Pratap Aggarwal, Chairman and Managing Director of IDS Infotech respectively.

Tyagi is first Chief of the Indian Air Force to be named in a corruption or criminal case by the CBI.

CBI sources said provisions of Prevention of Corruption Act have also been slapped in the FIR filed by the agency.

At least 12 teams of the agency also carried out coordinated searches at 14 locations across posh localities of Delhi, NCR and Chandigarh which include the residence of Tyagi, his cousins and offices of Finmeccanica, AgustaWestland, IDS Infotech and Aeromatrix among others, they said.

The agency has also named four companies--Italy-based Finmeccanica, UK-based AgustaWestland and Chandigarh-based IDS Infotech and Aeromatrix in connection with the case.

The sources said suspected European middlemen Carlo Garosa, Christian Michel and Guido Haschkhe, advocate Gautam Khaitan formerly associated with Aeromatric and its CEO Praveen Bakshi, former Finmeccanica Chairman Giuseppe Orsi, former AgustaWestland CEO Bruno SpagnoliniTyagi--Julie, Docsa and Sandeep have also been named in the FIR.

After carrying out its preliminary enquiry for nearly 16 days, the agency gathered evidence to register a case in connection with alleged payment of Ra 362 crore bribe to swing the 12 helicopter deal in favour of AgustaWestland, CBI sources said.

They said the agency has got some documents from Italy and files from the Defence Ministry which indicate criminal conspiracy to make alterations in the requirement of helicopter specifications which suited AgustaWestland.

The agency has also carried out detailed questioning of Tyagi, his cousins--Julie, Docsa and Sandeep, Gautam Khaitan, Praveen Bakshi and Bagrodia--last week, the sources said.

All the accused have denied allegations against them.

Italian company Finmeccanica allegedly paid a commission to the middlemen out of which huge sums were transferred to Indian nationals through Tunisia and Mauritius, the PE said.

The money was sent in the garb of of engineering contracts with two Indian companies IDS Infotech and Aeromatrix, it said.

The Italian agencies on February 15 had arrested Orsi, former Chairman of the Finmeccanica, parent company of AgustaWestland, on charges of paying bribe for the contract.

The investigation report by Italian prosecutor had claimed that Hashcke and Gerosa, through the Tyagi brothers, who in turn through their cousin S P Tyagi, managed first to change the tender details, in a way to favour, modifying the operational ceiling from 18,000 to 15,000 feet of altitude, thus allowing AgustaWestland spa (which otherwise could not have even submitted an offer) to take part in the tender.

The report also claimed that the duo managed to introduce a comparative flight trial with non-functional engine, thus facilitating AgustaWestland helicopters, the only ones which had three engines, swinging the deal in its favour.

It alleged payments were made to Hashcke and Gerosa through a consultancy contract between AW spa and Gordian Services Sarl and an amount of 400,000 Euros (about Rs 2.8 crore).

Out of this amount 100,000 Euros (Rs 72 lakh) were allegedly paid in cash to the Tyagi brothers (Julie, Docsa and Sandeep), it alleged.