Airport reopens but disruption ahead

LONDON, England (CNN) -- Flights were gradually resuming at Glasgow airports on Sunday following the attack the day before but British travelers were warned they faced a summer of disruption.

Some incoming flights were landing at Glasgow Airport on Sunday morning but officials said it would not fully reopen until later in the day.

Long queues of travelers hoping to board flights from Glasgow snaked around the airport.

Liverpool John Lennon Airport also reopened early Sunday morning after being closed overnight as police investigated a suspicious vehicle.

Travelers due to fly out of the airport in northwest England were told to contact airlines to check whether their flights will go ahead.

And British airports operator BAA said passengers hoping to board flights from Glasgow should check with their airline.

"It will be later in the day before we are able to get some departures out," spokesman Malcolm Robertson told the Press Association.

"Our advice to passengers is do not travel to the airport unless your airline has specifically confirmed your flight is going."

The Metropolitan Police carried out an immediate review of policing plans in London to ensure they were adequate for the increased threat level.

The United Kingdom has raised its terrorism threat level to "critical," the highest level possible, meaning attacks are imminent, after Saturday's incident in which a blazing car was driven into the terminal entrance at the Scottish airport. Watch flames spew from the car

Scotland Yard said in a statement: "Security at Heathrow Airport has been thoroughly reviewed, in conjunction with key partners, and we have introduced enhanced levels of policing and security.

"This includes increased patrols by armed officers and the closure of access to the forecourts."

Serious delays

The disruption is likely to continue over the summer. Even before the Glasgow incident, BAA warned that travelers should expect delays due to increased security at airports.

Last August there were serious delays and cancellations after the government introduced strict baggage regulations in the wake of an alleged terrorist attempt to blow up planes.

The rules have been relaxed to some extent since then, but earlier this year BAA, whose UK airports include Glasgow, Heathrow, Gatwick and Stansted said delays were likely this summer.

Virgin Atlantic Airways spokesman Paul Charles said passengers must allow more time to board their flights.

"Although the threat level has gone to 'critical' for the country it remains at 'severe' for airports and the impact is going to be on the approaches to airports," Charles told PA.

"People will have to allow more time to get to their flights and it's up to them to ensure that they arrive in good time. Airports are already very, very high security area."

Charles continued: "People work hard to save for their holidays and one should never underestimate the British desire, and almost desperation, to get away on their summer breaks. People will just have to understand that they will need to leave more time to get to airports."

Despite Saturday's attack at Glasgow, all of Britain's other airports will remain open with extra police guards but most are closing off roads leading to terminal buildings.

BAA said extra security measures would be in force at all its UK airports: Aberdeen, Edinburgh, Glasgow, London Gatwick, London Heathrow, London Stansted and Southampton.

Dropping off and picking-up passengers in front of the airports is severely restricted and there may be significant delays in reaching the terminal by car, the operator warned.

Travelers were recommended to use public transport to reach airports.

Kieran Daly, editor of online news service Air Transport Intelligence, said the difficulty was knowing how much security was needed at terminals and the approaches to them.

"With landside security, there is no difference between an airport and anything else," he told PA.

"It is a large building where people congregate, as they do in a nightclub.

"I would feel much more nervous about going to a club in the West End (of London) at the moment than going to Heathrow." E-mail to a friend

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