New Delhi, December 9: After a long investigation the Central Bureau of Investigation (CBI) today finally arrested Former Air Force Chief SP Tyagi over alleged irregularities in the AgustaWestland VVIP chopper deal involving Rs 3,600 crore. Along with SP Tyagi, his cousin Sanjeev Tyagi and a lawyer Gautam Khaitan has also been arrested after several rounds of questioning. SP Tyagi has been accused of misusing his official position for corrupt means and this is the first high-profile arrest made by the acting CBI chief Rakesh Asthana, who was recently appointed to the top job. The deal which was signed when Congress government was in power.Also Read - Govt Extends Tenures of CBI, Enforcement Directorate Chiefs Up To 5 Years; Issues Ordinances

Here are some facts you need to know about the controversial deal: Also Read - Aryan Khan's Arrest Highlights: No Mannat For SRK's Son, Bail Hearing Likely on Wednesday

1) The CBI had registered a case against the former air chief and 18 others, including European middlemen and his cousins, three years ago. Also Read - Dhanbad Judge Death Case: CBI's Report to Jharkhand HC Claims 'Judge Uttam Anand was Intentionally Hit'

2) SP Tyagi, a decorated officer has been repeatedly questioned on the deal with UK-based helicopter maker AgustaWestland. There are allegations that during the deal some Indian officials and politicians were allegedly paid to influence the contract for a dozen VVIP choppers bought for the President, Prime Minister and other top leaders of the country.

3) Retired Air Marshall Sanjeev Tyagi, who headed the Air Force between 2004 and 2007, is accused by investigators in Italy and India for helping AugustaWestland win the contract by tailoring specifications at the instance of his cousins.

4) There were reports that Sanjeev Tyagi entered into a consultancy deal with a middleman in 2004 when Air Marshal Tyagi’s cousins were certain that he would be the next air force chief and will be in a strong position to influence the deal.

5) According to NDTV reports, the investigators said that there is evidence that Air Marshal Tyagi met with a top official of Augusta’s parent company Finmeccanica when he was Air Chief.

6) There were some specific allegations against SP Tyagi that he reduced the required flying height for VVIP choppers from 6,000 meters to 4,500 meters which helped AgustaWestland to qualify for the controversial deal.

7) Air Marshal Tyagi had reportedly claimed that the change of flying height was a collective decision involving many departments.

8) The Enforcement Directorate which has been investigating the controversial deals claimed that the payments were made through Tunisia-registered companies controlled by Switzerland-based intermediaries Guido Hashcke and Carlo Gerosa and transferred to accounts in India and Mauritius.

9) After the controversial deal took place in 2013, three helicopters had been delivered to India.

10) The newly appointed CBI director Rakesh Asthana, who today ordered the arrest, has been in the news headlines over his appointment as the interim CBI chief. While on the other side the leaders of opposition had alleged that the government did not follow the rules for selection.