Bangkok Post

Sixty shopkeepers in this northwestern city received letters ordering them to burn the offending stock, including memory cards and speakers for MP3 players, and stick to selling only mobile phones and essential accessories.

DVD and CD shops have in the past been bombed by militants who deemed the businesses "un-Islamic".

In one of the letters, seen by AFP, militants wrote: "Do not compel us to send a bomber. ... Stop this shameless business in one week and burn the shameful stuff. Just sell mobile phones, batteries and chargers.

"Your markets have become centres of shamelessness. ... Our mission is to stop this shameless business and if you do not stop it yourself then we will make an example of you and your market."

Officials and police acted quickly to minimise the threat from would-be bombers.

"We have immediately closed down the shops doing ringtone and video clip business, after about 60 shopkeepers received threatening letters from Taliban by mail," local market association secretary Shakil Ahmed told AFP.

He said parking spots for motorcycles - which are sometimes packed with explosives and detonated - had been moved away from the market and police had been asked to increase security.

The Taliban has increased its campaign of violence in recent months, leading to fears that violence could mar a general election scheduled to take place by mid-May.