Police announced two new arrests Monday in the failed terrorist attacks at Glasgow's airport and in London, as security forces on "critical" alert pored over thousands of hours of surveillance video and evidence from suspects' houses and vehicles.
British officials have said they are hunting for what they called an al-Qaida-linked network behind the attempted terrorist attacks, and information also emerged suggesting that two of the suspects may be doctors working in Britain.
The intense hunt comes at a time of already heightened vigilance less than a week before the anniversary of the deadly July 7, 2005, London transit bombing. Those were largely carried out by local Muslims, exacerbating ethnic tensions in Britain.
In the latest attacks, two car bombs failed to explode in central London on Friday and two men rammed a Jeep Cherokee loaded with gas cylinders into the entrance of Glasgow International Airport on Saturday.
The unidentified driver of the Jeep, which burst into flames, is being treated for serious burns at Paisley's Royal Alexandra Hospital in Glasgow, where he is under arrest by armed police. A 27-year-old man also was arrested at the airport and was being held at a high-security police station in Glasgow.
It appeared authorities had been close on the trail of the airport bombers before the attack. Rental agent Daniel Gardiner, whose company leased a Glasgow-area home searched by police, said authorities contacted his firm just ahead of the airport attack, saying they had tracked phone records from it linked to the foiled London car bomb attacks.
Security in London was highly visible Monday morning, with long lines of cars forming behind police checkpoints on the London Bridge. Concrete car-blockers were in place protecting the Wimbledon tennis tournament.
Police in Glasgow said Monday that two more men were arrested the day before in the airport bomb attack investigation, bringing the total number of suspects in custody to seven.
Strathclyde police said the two men, aged 25 and 28, had been detained under the Prevention of Terrorism Act.
"This continues to be a fast-moving investigation," said Assistant Chief Constable John Malcolm.
Police Decline to Identify Suspects
Police have declined to identify any of the suspects, but British television and newspapers widely identified one as Mohammed Asha, a doctor working at the North Staffordshire Hospital, near the Midlands town of Newcastle-under-Lyme, where the police searched a house on Sunday. The hospital refused comment.
The man was arrested along with a 27-year-old woman when the police pulled over a car in a dramatic operation on the M6 highway in northwest England late on Saturday.
In Jordan, Asha's brother Ahmed told The Associated Press he had heard the media reports and said his 26-year-old sibling "is not a Muslim extremist, and he's not a fanatic."
"I can't believe this," he said. "It's nonsense because he has no terror connections."
Gardiner, an official at the Let-It house rental agency in Glasgow, said police contacted his company on Saturday afternoon, just minutes before the airport attacks.
"A card was put through one of my colleague's door, asking if we would contact them," he said. The colleague found the note at 3:05 pm British summer time, 10 minutes before the airport attack, Gardiner said.
"A couple of hours later, they (police) came back to us with a name, and we were able to trace their records," he said. "The police wanted to know why we had dialed a certain phone number. They had the phone records from the situation down in London."
Gardiner said the suspect tenant had a six-month lease on the house in Houston, a small suburb of Glasgow. He said the man was seen leaving the house wearing a stethoscope and was thought to be a doctor at the Royal Alexandra Hospital in Paisley on the outskirts of Glasgow. A controlled explosion was carried out Sunday on a car left at the hospital. Police said it was linked to the airport attack.
A British government security official said a loose U.K.-wide network appeared to be behind the London and Glasgow attacks, but investigators were struggling to pin down suspects' identities.
"These are not the type of people who always carry identity documents, or who use their real identities," the official said on condition of anonymity because of the sensitivity of the inquiries.
Media reports have speculated that the five suspects could include Iraqis, Iranians or Lebanese.
Home Secretary Jacqui Smith said in a series of broadcast interviews Monday that media reports about the nationalities of the suspects, which have been reported as possibly being Iraqi, Iranian or Lebanese, were "speculation."