Around 1.27 crore mobile connections were blocked in the last nine years, as those were used to bring in international calls through illegal voice over internet protocol (VoIP), according to the telecom division.

Of the SIMs (subscriber identity modules), around 1.16 crore were blocked by six mobile phone operators, said Tarana Halim, state minister for telecom.

The mobile operators suspended about 56.95 lakh connections in the last two years alone, she said.

Bangladesh Telecommunication Regulatory Commission conducted 244 raids in the last nine years, including 37 in 2015, and blocked 2.15 lakh SIMs, officials of the telecom division said.

The telecom watchdog also suspended another 8.75 lakh SIMs that were detected by the SIM Box Detection System.

BTRC in association with mobile phone operators introduced the SIM Box Detection System to detect illegal connections through random sampling.

“Illegal call termination is like smuggling. We want to bring an end to it,” Tarana said.

“We are working to ensure that all international calls enter the country through legal channels.”

Senior officials of a number of mobile operators said all SIMs used in illegal calls should be blocked, although their revenue falls with the increasing number of blocked connections.

The rate for each minute of incoming international call is 1.5 cents; incoming calls of around nine crore minutes route through legal channels every day.