**A man charged with trying to blow up a plane had been on a UK watch list, Home Secretary Alan Johnson has said.**He said Umar Farouk Abdulmutallab, 23, was refused a visa 14 months ago and was placed on a security list after he applied to study at a bogus college.
Meanwhile, UK passengers on US-bound flights face delays of up to three hours and extra security measures.
The Nigerian man targeted a Detroit-bound flight with explosives hidden in his clothes, it is claimed.
Police are searching several London properties linked to the Nigerian ex-University College London student.
Travellers are undergoing “pat-down” searches before boarding and being restricted to one item of hand luggage.