By Roland Buerk
BBC News, Dhaka
Mobile phone use is rising rapidly in Bangladesh
Bangladeshi authorities have ordered mobile phone operators to stop offering free calls after midnight, to protect the morals of young people.
A telecommunications regulator said it had received scores of complaints from parents that children were using the service to form romantic attachments.
They said children were losing sleep and some indulged in "vulgar talk".
Many people are conservative in Bangladesh, where arranged marriages are the norm and dating is discouraged.
In a letter sent to all five of Bangladesh's networks, the Telecommunications Regulatory Commission said the "free calls after midnight" offers were being abused by the young.
A senior official at the regulator told the BBC they had received scores of complaints from parents.
The rapid expansion of mobile phone use is driving social and economic change in Bangladesh.
By the end of last year, Grameen was signing up one million new customers every 40 days.
But many Bangladeshis are conservative, particularly when it comes to matters of the heart.
The country's biggest mobile phone operator, Grameen Phone, says it will meet its competitors to try to come up with a joint response.
The phone companies say they are surprised by the order, which the regulator says must be obeyed immediately.
One spokesman has been quoted as saying that if the authorities wish to stop young people meeting each other, by the same logic, fast food restaurants and universities should be shut down, too.