YALA, Thailand: Implicated by the wand of a "bogus" bomb detector, Hassan became one of hundreds detained in Thailand's insurgency-racked south because of equipment that experts say is useless.
Scandal over the Thai army's use of the GT200 detectors has deepened rancour towards the authorities in the Muslim-majority border region, where nearly 5,300 people have died in an eight-year conflict that shows no sign of abating.
Human rights activists say more than 400 people have been locked up - some for up to two years - on the basis of spurious evidence gleaned by the device, which is at the centre of a British fraud probe.
"I was playing football at my school when someone shot at soldiers nearby," said Hassan, who was held for 29 days without charge over the 2008 incident in Yala province - a hot-bed of violence.
"The soldiers entered the school looking for the gunman. They lined us up and used the GT200. The antenna pointed to me... and they took me away," he added, asking for his identity to be withheld because he fears reprisals for speaking out over his detention.
Billed as being able to detect minute traces of explosives, gun powder and even drugs, the GT200 is the army's main detection tool.
The hand-held device, which is claimed to be powered by the user's static electricity rather than a battery, is advertised as using a substance-detecting "sensor card" inside a plastic handle to trigger a twitch of its antenna in the direction of explosives.
Evidence debunking the powers of the GT200 - sold by Britain-based Global Technical Ltd - has long been in circulation, with experts describing it as little more than a radio aerial stuck on a useless piece of plastic despite the company's claims that it can detect explosives from hundreds of metres away.
In July the man behind the GT200 was charged in Britain with "dishonestly representing" the device as "capable of detecting explosives".
Several other British businessmen are awaiting trial for selling similarly defunct equipment around the world - including to Iraq.
A Thai government probe concluded the device works only 25 percent of the time, a success rate critics attribute to nothing more than random chance.
"Tossing a coin would be more accurate," said Angkhana Neelapaijit, of the Justice for Peace foundation, which uncovered the scandal.
"People in the south knew the GT200 was fake from the first time it was used" in 2007, she said. "But the Thai authorities refused to listen... all trust in the government and army has been lost."
Thailand's highest investigating agency is now mulling legal action against Global Technical and its Thai distributors.
But the powerful military has refused to concede it was duped over its rumoured $20 million acquisition, or apologise to those held in what rights groups say is a flagrant miscarriage of justice.
Hassan said he was threatened and interrogated in detention and forced to point out friends from a school photograph.
Among them was Ayub who said he was arrested with no further evidence and held for two years before he was freed without a conviction or an apology.
"I'm so angry. They took two years away from me but I am scared it can happen again," Ayub told AFP, also asking for his identity to be protected.
He said he now carries the stigma of having been accused of links to the militants, who are believed to want greater autonomy and kill both Buddhists and Muslims in near-daily bomb or gun attacks.
The Thai army refutes accusations of arbitrary detentions based on the faulty device.
"We found real evidence - guns, weapons, grenades - that's why we arrested them," Colonel Pramote Promin, deputy spokesman for the Internal Security Operations Command said, addressing the wider issue of detentions.
"It might be a hallucination but we found (weapons) many times. It might be a fluke or coincidence that it worked," he said, adding that the effectiveness could be "something above science".
Despite his endorsement, the army appears to have stopped mass round-ups of men for "wanding" by the device, which were commonplace between 2007 and 2010, according to locals in Yala and Pattani provinces.
But soldiers still check cars and roadsides with the device, raising fears its continued use is exposing the security forces - and civilians they are supposed to protect - to greater risks.
"It's a big scandal," said Jessada Denduangboripant, a biologist at Bangkok's Chulalongkorn University who was one of the first Thai experts to question the device.
He is sceptical that a probe by Thailand's top investigative body will apportion blame to the "powerful people" behind the purchase of the detector.
But as long as authorities refuse to admit fault, victims will continue to be denied justice, said Kaosar Aleemama of the Muslim Attorney Centre, which represents Hassan and Ayub.
"These people have never heard someone say 'I am sorry' for taking their freedom," she added. "It is an issue of human dignity." (AFP)