Chaos at UK airports over terror alert
All flights into London Heathrow have been cancelled, except those already in the air, due to a terrorist alert.
Severe delays are occuring at all UK airports due to heightened security.
British Airways has cancelled all its short-haul UK and European inbound and outbound flights to and from Heathrow until 3pm.
Lufthansa, Air France, Iberia and Olympic have all cancelled flights to the UK.
Monarch said no flights have been cancelled and 50% of scheduled flights departing from Gatwick, London Luton, Manchester and Birmingham have left within one hour of scheduled departure time, with all remaining flights departing within three hours.
Most airlines, however, are urging travellers to stay at home unless their travel is essential.
Passengers who decide to fly have been banned from taking any hand luggage on flights, creating long queues at check in.
Home secretary John Reid said a major terrorist plot to bring down a number of aircraft mid-flight had been detected.
It is believed the plan was to smuggle explosives onto as many as 20 flights.
About 20 arrests are reported to have been made overnight.
The UK government has posted information for travellers and the travel industry on the Home Office, the Department for Transport and Foreign Office websites.
ABTA has issued advise to members at http://www.abtamembers.org/disruptionadvice.shtml
See other stories for more detail of disruptions.
By Bev Fearis
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