The summon notice was dispatched to their offices in New Delhi and Bengaluru.
Vijay Mallya exited USL after he sewed a deal of $75 million (Rs 515 crore) with its majority owner, Diageo.
"Questioning is required to understand the purpose of the deal, as we suspect collusion between the two firms," a senior ED officer told Business Standard.
As per media reports, Diageo completed the transaction of majority stake (54.7%) in United Spirits in July 2014 and has been pushing for Mallya's resignation from chairmanship. Mallya stepped down in February after striking the deal.
The ED believes the entire deal was planned for the purpose of diverting funds. 'We have collated the balance sheet of USL that showed the diversion of nearly Rs 600 crore by Mallya in 2011. This can be a case in this deal as well," the ED officer said.
Diageo plc acquired a 54.8% shareholding in United Spirits making India one of its largest markets.
Soon after the deal, Mallya fled to the UK, keeping in dark the consortium of 20 banks whom he owes Rs 6,963 crore. Mallya has been paid $40 million as the part of the first instalment by Diageo without informing any of the government agencies. The ED, along with other central agencies, is probing allegations of money laundering with respect to the loan amount.
Among the other criteria of the deal that raises suspicion is the clause of suing. According to clause, Diageo and Mallya agree they won't sue each other post deal settlement.
Meanwhile, the enforcement agency has sent the reasons/response sought by Interpol on issuing Red Corner Notice (RCN) against Vijay Mallya. An RCN is issued "to seek the location and arrest of wanted persons with a view to extradition or similar lawful action" in a criminal case probe.
The agency was asked to furnish evidences available against Mallya, the details of the other accused in the case, and the offence based on which the agency registered a case under the Prevention of Money Laundering Act (PMLA) in connection with Rs 950-crore IDBI bank loan fraud case.
