The telecom regulator has recently urged law enforcement agencies to help it find out illegally registered SIMs and take legal actions against the culprits who are selling such mobile connections.
The enforcement division of Bangladesh Telecommunication Regulatory Commission made the call in a letter to the inspector general of police.
BTRC also requested police to give the details of the illegally registered SIMs, which were seized by law enforcers in recent drives.
The regulator plans to fine the mobile operators $50 for each illegal SIM, officials said.
The SIM re-registration process was successful, and only some dishonest retailers and distributors biometrically registered SIMs with duplicate fingerprints and national identity cards of other users, reads the letter signed by Md Towfiqul Alam, an assistant director of BTRC.
The culprits took the advantage of customers' unawareness, according to the letter.
Now the retailers or distributors are making money by selling those SIMs at high prices in the open market. Police had earlier seized lots of SIMs which were re-registered illegally in different parts of Dhaka, Chittagong, Mymensingh and Natore.
The country's six mobile operators re-registered 11.60 crore SIMs through biometric verification under a process that started on December 16 last year and ended on May 31 this year.
The government also plans to take an initiative to cross-check the information of the re-registered SIMs with the database of the Election Commission to find out which mobile connections bear duplicate fingerprints or fake national identity cards.
The Election Commission may lead the initiative, for which a meeting was held at BTRC office in presence of State Minister for Telecom Tarana Halim and senior officials of the National Identity Registration Wing (NIDW).
However, the government is yet to take a decision on how to cross-check the information, said Brigadier General Sultanuzzaman Md Saleh Uddin, project director of NIDW.