Dogs could sniff bomb out better than GT200

In response to reporters' angry questions about the British-made scanner, Army chief Anupong Paochinda shot back: "Is the company using you to ask these questions?"

Joint Military Police Civilian Taskforce commander Lt-General Kasikorn Kirisri said the GT200 scanner was very useful in detecting and preventing explosions in the deep South, where violent incidents on an almost daily basis have killed more than 3,900 people to date.

"Not using the bomb detector may affect efforts to restore peace in the deep South," he warned, adding that there might have been some problems with the detector, but they mostly involved human error.

Fourth Army Region Commander Lt-General Pichet Wisaichorn said the military would continue using the equipment in the South until it had something else.

However, the police believe the bomb detector is not effective enough, with only a 30-40-per-cent reliability factor, which means the chance of it failing is higher than succeeding.

"It is not accurate. If the operator is too close to the target - less than 3 metres - it will not work," said Pol Senior Sgt-Major Chan Warongpaisit, who regularly operates the equipment in the South.

Meanwhile, the BBC reported the UK had banned the export of ADE651 and other similar bomb detectors to Iraq and Afghanistan because they did not work.

Just like the ADE651, no tests have proved the GT200 to be totally effective. Yet manufacturer Global Technical claims it can detect all kinds of explosive substances and narcotics within a 700-metre radius on land and 800 metres under water.

The GT200, powered by the movements of the operator, becomes active when the operator is moving and starts receiving signals from the magnetic signature of the targeted substance, the company says on its website.

Yet, the GT200 failed to detect many bombs in the deep South, which led to several tragic incidents. Last October, two bombs killed two people and injured dozens of others in Yala and Narathiwat provinces after the so-called bomb detector failed to detect any explosive devices in the area. However, military officials say the operators were in an excited state, which prevented the equipment from working properly.

In reality though, bomb detectors like the GT200 have never succeeded in double-blind tests. A test of the equipment conducted for Thai authorities by a sales agent resulted in a "random chance" finding, which meant a sniffer dog would be better at detecting explosives.

A 1999 guideline from the US Justice Department regarding commercial explosive-detection systems said so far, there were no devices that could successfully detect specific materials like explosives as part of controlled double-blind tests.

The GT200 was previously known as the Mole substance detector, but the manufacturer changed its name because the Mole detector failed to pass scientific testing in the US, one expert said.

An Chulalongkorn University engineer said the bomb detector was being used in the deep South as if it were a magic dowsing rod.

Meanwhile, residents in the South wonder if officials believe the device is a lie detector, because they always use it when trying to prove if any suspects - held over suspicions of having made or planted bombs - had contact with explosive substances.

Human-rights defender Pornpen Khongkajornkiart said many fellow activists questioned the GT200's effectiveness and advised the government to review the equipment and conduct tests to prove its quality.

Meanwhile, Dr Pornthip Rojanasunand, director of the Forensic Science Institute and who always uses the GT200, said the UK had only banned the ADE651.

She said the detector was effective when searching for bombs and even nails under water.