Bangkok - Not too long ago, militants in southern Thailand who used their mobile phones to detonate bombs relied on prepaid SIM cards to cover their tracks. Now that the government has tightened controls by requiring the registration of all prepaid SIM cards, the authorities fear that the militants may turn to another strategy: Use the mobile phones of complete strangers.
The Southern Border Provinces Peace-building Command (SBPPC) on Nov 27 warned residents in the restive South not to return missed calls from unknown callers because their cell phones could be manipulated to act as triggers for explosives.
On Nov 15, phone operators suspended services to unregistered prepaid mobile phones in southern Thailand. SBPPC spokesman Somkhuan Saengprathranet said since the new registration rule kicked in, militants are loathe to use their own mobile phones for triggering bombs because they could be traced.
A new tactic they may adopt is to call a number at random and hang up, thereby leaving a missed call message on someone's phone. A returned call sets off the bomb, Mr Somkhuan said.
"So please don't rush to return calls immediately after a missed call. If the person who has called you really wants to talk to you, he will call back," he said.
Mobile phones can be used to set off explosions because they generate electricity, which can be channelled to activate a trigger device.
In the past two years, mobile phones have been used frequently to trigger explosions in the Muslim-majority south, where more than 1,000 people have died since violence escalated in January last year.
* Police warn of threat of 'missed call' explosions (The Nation, Nov 28)