Taliban militants are threatening to blow up Afghan telecommunications towers if mobile phone companies do not shut down their networks at night.

Taliban spokesmen said Monday that U.S. and other foreign troops in Afghanistan use mobile phone signals to track down Taliban fighters.

They demanded that phone operators switch off their signals every day from 5 p.m. local time (1200 UTC) until the early morning. The Taliban spokesmen say the phone companies have three days to meet the demand or face attacks on their towers and offices.

Mobile phones were introduced in Afghanistan after the fall of the Taliban in 2001. They are now the country's principal means of communication and are used by Taliban militants to talk to each other and the media.

Communications experts say the U.S. military can pick up mobile phone signals using satellites, without help from phone companies.

The Taliban has threatened mobile phone companies in the past, accusing them of colluding with foreign troops in Afghanistan.

Afghanistan has four mobile phone companies: Afghan Wireless, Roshan, Areeba and Etisalat.

Some information for this report was provided by AFP, AP and Reuters.