The BTRC made the order on Wednesday in a meeting with representatives of the operators.
BTRC Chairman Sunil Kanti Bose told bdnews24.com that the operators were given five instructions to trace the SMS senders.
He said the operators would soon begin work on the instructions.
Bose declined to elaborate the instructions. “The five instructions cannot be divulged for security reasons,” he said.
Scores of users in Bangladesh received SMSes on Monday and Tuesday from unknown senders on execution of Molla, who was convicted of war crimes during the country’s Liberation War in 1971.
They said the country would face a civil war if the Jamaat leader was hanged.
The government earlier announced that Molla would be hanged on Tuesday midnight but the Supreme Court’s Chamber Judge stayed the execution few hours before the time.
A top official of BTRC told bdnews24.com the SMSes were being sent from abroad in the last several days. “They could have been identified easily had they been sent from inside the country.”
He said the operators had to install some new technologies to identify overseas SMS senders.
Earlier on Jun 23, unknown people sent SMSes with a call to say ‘no’ to the chiefs of the two major political parties.