Hyderabad, June 14 -- An illegal telecom operation running in Secunderabad was busted by the Department of Telecom (DoT) Hyderabad unit, in coordination with Telangana police, late Thursday night, June 12.

Based on detailed analysis and intelligence, officials traced an unauthorised setup using SIP (Session Initiation Protocol) connections, operated by a private firm in Hyderabad. The setup was being used to illegally route international calls from countries like the Middle East and the United States to Indian users, while displaying fake local Indian numbers.

During the raid, authorities seized an SIP server, three laptops, one monitor, and other network equipment used in the operation.

Officials said such illegal setups lead to signi...