Tyagi arrived at the zonal office of the agency here just before 11 AM and left around 9:30 PM. He did not talk to the waiting media outside.
Agency sources said he was questioned about his role in the deal and his statement was recorded under the Prevention of Money Laundering Act (PMLA).
The retired Air Chief Marshal was questioned in the same case by CBI for the last three days but this is for the first time he was summoned by the Enforcement Directorate.
He may be summoned again, they added.
Agency sources had earlier indicated that Tyagi's questioning was necessary in the light of a recent judgement of a Milan (Italy) court which had sentenced Italian defence and aerospace major Finmeccanica's former chief Giuseppe Orsi and the former CEO of the firm Bruno Spagnolini on corruption charges in the sale of a dozen AgustaWestland helicopters to India for VVIP purposes.
Tyagi's name cropped at various points in the said judgement.
He took over as the Indian Air Force chief on December 31, 2005 and retired from service in 2007.
ED had registered a PMLA case in this regard in 2014 and named 21 people including Tyagi in its money laundering FIR. It had also arrested Delhi-based businessman Gautam Khaitan and had also filed a charge sheet last year.
ED had earlier submitted that Khaitan was on the board of Chandigarh-based company Aeromatrix which was allegedly a front firm for the financial dealings in the chopper deal.
On January 1, 2014, India scrapped the contract with Finmeccanica's British subsidiary AgustaWestland for supplying 12 AW101 VVIP choppers to the Indian Air Force (IAF) over alleged breach of contractual obligations and charges of paying kickbacks to the tune of Rs 423 crore by it for securing the deal.
The central agency has also issued Letters Rogatory (judicial requests) to ten countries in this case.
ED is excpected to question Tyagi's cousin Sanjiv Tyagi alias Juli tomorrow.
