Thursday, August 10 2006 18:51 Hrs (IST) - World Time -

London: Britain was placed under the highest 'crucial' alert early today (Aug 10, 2006) ahead of a massive counter-terrorism operation to disrupt 'a major threat to the UK and international partners', Home Minister John Reid said. The minister was making a statement after a plan to blow up nearly 10 aircraft in the air was foiled, leading to flight cancellations and the arrest of 21 terror suspects.

"Overnight the police, with the full knowledge of ministers, have carried out a major counter-terrorism operation to disrupt what we believe to be a major threat to the UK and international partners," said Reid.

"Police, acting with the Security Service, MI5, are investigating an alleged plot to bring down a number of aircraft through mid-flight explosions, causing a considerable loss of life. The police believe the alleged plot was a very significant one indeed.

"At 2 a.m. this morning the Joint Terrorism Analysis Centre raised the UK threat state to its highest level 'Critical'," Reid said.

The minister said this was only a precautionary measure.

"We are doing everything possible to disrupt any further terrorist activity. This will mean major disruption at all UK airports from today. But as far as is possible we want people to go about their business as normal," he sia.d

British Transport Minister Douglas Alexander said, "Earlier this morning all UK airports and all airlines operating in to and out of the UK were asked to implement a heightened level of security and this step has been taken to ensure maximum security on all flights so people can go ahead with their travel arrangements. "

"However, ensuring maximum security unfortunately will involve immediate and severe disruption for passengers with significant delays likely at all UK airports," Alexander said in a statement.

"What these changes mean in practice is that all hand baggage will now have to be checked in with only a small number of essential items allowed through search controls. Exceptions will be in place for those travelling with infants and for prescription medicines," he said.

"Extra security arrangements will be in place for flights to the USA. Passengers wanting detailed information on these new arrangements for their individual flight should contact the airline they are using.

"Additionally advice on what will be allowed as hand luggage is also available on the Home Office, Department for Transport and Foreign Office web sites," the transport minister said.

Alexander assured, "This heightened level of security will last only as long as the situation demands, we will keep this under review."