UK airports on alert over 'human bomb' terror attack fears

Airports across the United Kingdom have been placed on terror alert over fears that fanatics from Yemen and Syria have joined forces to plot a "stealth" bomb attack.

According to The Mirror, Al-Qaeda's top bomb maker Ibrahim Hassan al-Asiri is reportedly working on a device that can evade scanners and be hidden inside a terrorist's body or electronic gadgets, and his Yemen-based team are feared to have made the 'human bombs' after linking up with jihadis in Syria.

The country's security chiefs fear would-be bombers could be equipped with European passports and be groomed to slip out of the country and use the deadly new technology to blow a plane out of the sky.

Extra security checks are being carried out in a bid to thwart them.

Britain's Deputy Prime Minister Nick Clegg has urged passengers to exercise patience and warned that the extra security precautions could be here to stay.

The tightening of airport security comes hours after the United States ordered airports on routes to American cities to step up security after picking up a "credible" terror threat. CIA agents have reportedly found some bombs can be made with a couple of ounces of liquid explosives and a non-metallic detonating device, and can be surgically implanted into would-be bombers or hidden in electrical devices or shoes with little possibility of detection.

U.S. Homeland Security Secretary Jeh Johnson said in Washington that extra security measures would be "both seen and unseen" and would be used in a bid to thwart all terrorists attempting to launch attacks on the country.

The alert had an immediate impact on security for trans-Atlantic flights. Passengers face extra bag searches at departure gates and along with second checks on shoes, laptops, iPads and other battery-powered gadgets. Staff are also swabbing all electronic items, clothing and shoes to check for traces of explosives. Shoes and belts had to be removed and travellers were subject to "vigorous" physical searches.