The accused have been identified as Subham (23), Mohit Khanna (50), Bhupinder Singh (32) and Rahul Makhija (22), they said.
Police said that 28 telecallers have also been bound down.
The cyber cell police station of outer district on May 31 received a tip-off about an illegal call centre being run in Rani Bagh area.
According to police, the accused persons were involved in large scale cyber cheating with US citizens by impersonating as the executives of Microsoft support team from the US. They cheated their targets by inducing them to pay money for solving a non-existent problem, police said.
“A raid was conducted at the call centre premises during night where more than 25 persons, including females, were found engaged with computers in two separate halls. Computer sets and accessories were installed to communicate with the US citizens. These telecallers would call US nationals with English names in order to impersonate themselves as Microsoft support executives from the USA,” said Sameer Sharma, Deputy Commissioner of Police (Outer).
They used illegal techniques like VoIP (Voice over Internet Protocol) calling, causing loss to government exchequer, he said.
They also used remote access applications such as Ultraviewer, TeamViewer and AnyDesk. The dialling software was checked and a list of US telephone numbers in the dialled and received calls was found, he added.
Interrogation revealed that one of the accused, Subham, who holds BTech in computer science and earlier worked in BPOs, has good knowledge of computers and call centres while Mohit, along with other accused persons, conspired to form their own call centre, the senior police officer said.
Elaborating about their modus operandi, the officer said that the accused themselves first created problems and malfunctions in the systems of US nationals and their team members would call their targets by impersonating as US-based executives.
“They were cheating US nationals on the pretext of solving a non-existent problem, created by them by charging hefty amounts. During that, they sometimes took the computer systems of the victims on remote access through various applications. They even guided the targets to take a gift card and later also took the gift card number from them,” said Sharma.
The gift card numbers so obtained were sent to the exclusive telegram group of the office in which a few blockers (their accomplices) used to utilize those gift cards for purchasing cryptocurrency, mainly Bitcoin, which are to be transferred to Bitcoin address given in the group by the owner or team leader, the officer said, adding that this way, they had been cheating foreigners since long.
As many as 29 smartphones, 25 hard discs from different CPUs, two laptops, one DVR, three routers and one load balance router have been recovered from the accused, police said.