BEIRUT/BAGHDAD — At a checkpoint in central Beirut, a guard checks a small truck for explosives. He is manning the last security barrier before Lebanon's parliament building 100 meters away, and relying on a bomb detector that experts say is useless. Holding the device, a swiveling telescopic antenna mounted on a black plastic handgrip, the plain-clothes guard walks by the side of the truck. It does not respond, and the truck is allowed to pass. At the nearby marina where millionaires' yachts are moored by the glistening Mediterranean Sea, and at entrances to the underground parking of an upmarket shopping mall, the same bomb detectors are used. They have been a familiar sight at checkpoints across the Middle East for about a decade, acquired for thousands of dollars apiece by authorities desperate to contain deadly waves of bomb attacks. But the devices — which have even been sold to UN peacekeepers — have been condemned by forensic specialists as a dangerous waste of money, based on bogus science. Marketed under names such as ADE651, GT200 and Alpha, they are supposed to respond to the presence of explosives, causing their metal antenna to swivel on a hinge toward the material. Britain imposed export bans on ADE651 and GT200 detectors in 2010, warning they were fake, and the British businessmen who made millions of pounds by manufacturing and selling them around the world were subsequently sentenced to jail. Yet is was only this month that Iraqi Prime Minister Haider Al-Abadi — whose country bought hundreds of ADE651 devices eight years ago — ordered his security services to stop using them, after a huge truck bomb killed 292 people in Baghdad. And devices of a similar design were seen by Reuters correspondents being used at checkpoints in countries including Lebanon, Syria and Egypt in recent weeks or months. Scientist Dennis McAuley said he examined a device of a similar design to the ADE651 and GT200 when he worked at Northern Ireland's Forensic Science Laboratory. He took it apart to see how it worked. "There is no scientific basis to it. It's a complete fraud," he told Reuters. "If authorities are putting any reliance on this to detect explosives, it's ludicrous. It's unbelievable they are still using this." 'Objects with no value' In Egypt, a soldier was seen using one of the wand-like devices this month at a checkpoint in Ras Sidr, checking cars waiting to pass through a tunnel in Sinai. The equipment was used in conjunction with thorough searches of the vehicles. Egyptian military spokesman Brig. Gen. Mohamed Samir said any equipment bought by Egypt "is subject to specific standards and is tested before the contracts are signed". In the Syrian capital Damascus, frequently targeted by rebel and militant bombings during Syria's five-year-old conflict, guards outside a hotel and a government complex were seen carrying similar-looking devices in April. In Beirut, where twin suicide bombings killed 44 people in November, officials declined to comment about the detectors, although guards in the city who were using them this week said they were effective. One said he discovered a concealed package in a car, but did not say whether it contained explosives. While specific devices seen by Reuters correspondents in Lebanon, Syria and Egypt could not be individually identified, they were of a similar design to the ADE651 and GT200 detectors which Britain imposed export bans on. Dan Kaszeta, managing director of London-based security consultancy Strongpoint Security, and a graduate of the US military's Explosives Ordnance Disposal school, said no device could work based on the concept of an aerial swiveling in response to traces of explosives it detects. "Given the state of current technology there is nothing that is in hand-held use that remotely detects explosives with any degree of accuracy or specificity. It just does not exist."