Maharashtra ATS Deputy Commissioner of Police Vinay Rathod said that the gang is suspected to have cheated the exchequer of revenue worth an estimated Rs 37.50 crore.
"We are investigating whether this gang may have links with terrorists or terror and anti-national organisations, since the names of the caller and called parties are not known in such illegal telephone exchanges. We also probing the gang's connections to 'hawala' operators," Rathod said.
The accused arrested on Friday are: Faisal Batliwala, 28, Sameer Deoraj, 30, Nasseem Khan, 29, Imtiaz Sheikh, 38, Hyssain Syed, 39, Mandar Achrekar, 36 and Sibtan Merchant, 33, and the raids were carried out at their homes and shops in five locations.
Giving details, he said that the seven ATS teams nabbed the seven accused after raiding five locations in Mumbai, Raigad and Thane.
They are Govandi, Masjid Bunder and Worli (Mumbai), and Panvel and Kalyan in Raigad and Thane, respectively.
The ATS has also seized a Dell server, nine inboxes, three laptops, four desktops, seven WiFi routers, two Internet Terminating Switches and 11 cellphones and 513 SIM cards, totally valued at around Rs 6.50 lakh.
"Since such a huge quantity of SIM cards were recovered, we suspect that they may be acquired using fake papers. That could be a separate racket which we shall probe in collaboration with the Department of Telecommunication," Rathod said.
The modus operandi employed by the accused was to route phone calls through the illegal telephone exchange through the routers and earn crores of rupees by 'stealing' calls from different government departments.
Besides, they also routed incoming calls to India from abroad by routing local numbers through the UAE and other countries.
( With inputs from IANS )