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LONDON - Britain is at "critical" risk of a terror attack following two failed car bombings and an attack on Glasgow Airport, the Home Office has said.
Two men rammed a petrol-filled, four-wheel-drive vehicle into Glasgow airport on Saturday (Sunday morning NZT) in what police called a terrorist attack.
The Jeep Cherokee was engulfed in flames and the men were arrested -one taken to a hospital in critical condition with burns.
Scotland Yard said counter-terrorism officers later arrested two more people on a motorway in northern England "in connection with the events in London and Scotland on the 29th and 30th of June".
"I can confirm that we believe the incident at Glasgow airport is linked to the events in London yesterday," the top police officer in the Glasgow area, Willie Rae, told reporters.
"There are clearly similarities and we can confirm that this is being treated as a terrorist incident."
Britain was placed on "critical" alert after the incident. The security rating is the Home Office's highest and indicates an attack is expected imminently.
Prime Minister Gordon Brown, in office for just four days, convened a meeting of the top security committee on Saturday.
"I want all British people to be vigilant and want them to support the police and all the authorities ... I know the British people will stand together united, resolute and strong," he said.
The attack came barely 36 hours after police thwarted a possible al Qaeda plot in London.
Metropolitan Police have been scouring hours of CCTV footage since a vehicle packed with up to 60 litres of fuel, several gas canisters and a large quantity of nails was found early on Friday morning.
A mobile phone, which security experts believed might have been a detonation device, was left inside the fume-filled car.
A second Mercedes packed with gas and nails was later found to have been parked just a few hundred yards from the first.
The foiled plot came to light two years after a coordinated attack by suicide bombers on London's transport system killed 52 commuters.
Attacks linked
Strathclyde Police Chief Constable Willie Rae confirmed late on Saturday night that the failed bombings and the attack in Scotland were connected.
"I can confirm that we believe the incident at Glasgow airport is linked to the events in London yesterday," he said.
"There are clearly similarities and we can confirm that this is being treated as a terrorist incident."
Rae said that one of two suspects detained after the attack and taken to hospital with severe burns had been found to be carrying a "suspect device", but did not elaborate.
He said the device, which he would not confirm was a suicide belt, was found on the man's body. The suspect was in critical condition, he said.
"When he was being treated at the hospital a suspect device was found at the hospital ... as a consequence of that the hospital was partly evacuated until this device was removed and put into a safe area."
He said Strathclyde police would be working closely with London's Metropolitan police in the days ahead as they investigated the ties between the twin car-bomb plot uncovered in London early on Friday and the Glasgow incident.
Absolute chaos
Witnesses described seeing passengers scatter as the jeep hit the airport terminal at about 3.10pm local time (2.10am Sun NZT).
"It raced across the central reservation and went straight into the building," said taxi driver Ian Crosby outside the terminal.
"There was absolute chaos," said a witness, James Edgar.
"[The driver] was very close to getting to a place which was holding maybe 200 people. There was no emotion on his face whatsoever. He was very passive. The crowd were shouting at him, but he just stared straight ahead."
According to several onlookers, the men inside the Jeep tried to intensify the blaze by pouring petrol from a canister.
One, his clothes on fire, was struggling with the police on the floor of the terminal when he broke free and tried to open the boot of the vehicle, but he was dragged away.
"The man was on fire," said Robin Patterson, from Rochester in Kent.
"He looked like something from a horror film. His skin was peeling; his hair was all burned. You couldn't see what colour he was, just that he was a big man.
"It was pretty shocking to see. I've never seen anything like it. Obviously if you drive a car into a big wall it doesn't automatically set on fire like this. You don't think it would happen in Scotland, in a place like Glasgow."
Television footage showed fire crews still attempting to extinguish the blazing vehicle several minutes after it crashed into the terminal.
Part of the canopy sheltering the pavement outside was also on fire.
Scott Leeson was waiting for a colleague on an arriving flight.
"Fortunately his plane was delayed," he said.
"There were a couple of explosions. Maybe it was petrol going off. My main concern was to ring my colleague with his young family. He would have been coming out of that door had his plane not been delayed.
"Fortunately there was a lull at that point, and there weren't as many people around. If it had happened 10 minutes earlier, there would have been fatalities."
Security analysis
But experts drew some comfort from the fact that none of the attacks had so far succeeded in causing mass casualties.
According to one report, the would-be bombers in London tried to detonate each car bomb twice, without success.
Had they succeeded, experts believe that the conflagration and resulting explosions would have created huge fireballs and blasted nails and metal fragments over a 100-yard radius, killing or maiming anyone within range.
An explosives expert said the failure of the attempted bombings in London "shows that the security service clampdown on bomb-making materials, like buying large quantities of fertiliser, is working.
These terrorists have had to resort to buying petrol and gas canisters, which would not raise any questions. As a result, the bomb may be lethal, but not on the same scale as Semtex bombs."
The Glasgow attempt appeared to confirm his point.
Lord Carlile, the independent reviewer of terrorist legislation, urged people to be "vigilant in the extreme".
He warned that car bombs were cheap and easy to make, and may be replicated by other terrorists.
"I am not the least surprised that the violent jihadists have moved on to car bombs," he added.
He predicted extended police powers to stop and search.
"There is a long history of car bombs in Baghdad and Israel. People must be vigilant in the extreme and be prepared to report things they would not normally report. Once a campaign of cheap and very easily made vehicle bombs has started it has the potential for persistent repetition."
A security analyst said the terrorists' apparent inability to carry out "spectaculars" could mean a switch of tactics to attacks aimed at "making the public feel uneasy wherever they go".
He added: "We may see a period where there are a lot of attempts to use car bombs around the country."
Edward Davey MP, chief of staff to Sir Menzies Campbell, the Liberal Democrat leader, said: "The British people will not be cowed by these attacks, and we must defend our way of life and traditions at all costs."
Dame Pauline Neville-Jones, former head of the joint intelligence committee, told Sky News: "This is a very young government, and we may yet see further attacks.
We are seeing a pattern of attack in the early days of a new government."Hours before the Glasgow incident, the Home Secretary, Jacqui Smith, had urged the public to remain vigilant.
Emerging from a Cobra security co-ordination committee yesterday morning, she said: "We were updated on the police operation and the Prime Minister took the opportunity to thank the police and the security services for all their hard work over the last 48 hours.
The Prime Minister stressed that all parts of the Government have got to work together to combat the terror threat.
"I am satisfied that across Government and with the police and agencies, we are doing all we can to protect the public.
"The police are clear that the most important contribution that the public can make is to carry on reporting anything suspicious and to be vigilant, and I would ask them to do that.
"But I must stress that we mustn't let the threat of terror stop us from getting on with our lives."
- INDEPENDENT/REUTERS
