GLASGOW, Scotland -- British police focused Tuesday on at least four physicians with roots outside Britain - including a doctor seized at an Australian airport with a one-way ticket - in the investigation into failed car bombings in Glasgow and London.
Separately, two men were arrested in an industrial park in northwestern England under the Terrorism Act on Tuesday, but a statement from Lancashire police said it was "too early to confirm whether or not these arrests are linked to recent events in London and Glasgow."
At least four of the eight suspects directly tied to the terror investigation were identified as doctors from Iraq, Jordan and India. One of the doctors from India, 27-year-old Muhammad Haneef, was arrested at Brisbane's international airport where he was trying to board a flight, the Australian attorney general said.
British media reported that at least two people detained Sunday were trainee physicians.
Mark Shone, a spokesman for Halton Hospital in England, said Haneef worked there in 2005 as a temporary doctor, coming in when needed. He also confirmed a 26-year-old man arrested in Liverpool late Saturday - also Indian - practiced at the hospital but he would not provide the man's name or further details.
British media reported that at least two people detained Sunday in Scotland were trainee physicians.
Amid increased security at British airports, train stations and on city streets, a bomb disposal team carried out a controlled explosion Tuesday on a suspicious car parked outside a mosque in Glasgow.
Strathclyde Police Superintendent Stewart Daniels told the British Broadcasting Corp. there was "absolutely no specific information" of a threat from the vehicle but that it had been detonated as a precaution.
On Saturday, two men rammed a Jeep Cherokee loaded with gas cylinders into the terminal at Glasgow's airport, then set the vehicle on fire. On Friday, two car bombs failed to explode in central London.
Police were also investigating an attack on an Asian news agent early Tuesday in Glasgow, in which a car was rammed into the shop and caught fire or set ablaze, and the torching of a real estate office next to a mosque near Edinburgh on Monday.
Police have yet to establish if either attack was racially motivated, but Osama Saeed, Scottish spokesman for the Muslim Association of Britain, said tension was increasing.
"While some crimes will be just committed by one person themselves, quite often there are groups of people," he said. "It suggests there is a rising feeling of hostility where people feel comfortable in the company of others acting in a grotesque fashion."
A British security official said Monday that Pakistan and several other nations were asked to check possible links with the suspects. British-born terrorists behind the bloody 2005 London transit bombings and others in thwarted plots here were linked to terror training camps and foreign radicals in Pakistan.
Authorities said police searched at least 19 locations as part of the "fast-moving investigation," which has come at a time of already high vigilance before the anniversary of the suicide bombings in London that killed 52 people on July 7, 2005.
The British government security official said investigators were working on one theory that the same people may have driven the explosives-laden cars into London and the blazing SUV in Glasgow.
The unidentified driver of the Jeep was being treated for serious burns at Royal Alexandra Hospital in Glasgow, where he was under arrest. Bomb experts carried out a second controlled explosion on a car at the hospital Monday, after a similar blast Sunday. Police said the car was linked to the investigation, but no explosives had been found.
Authorities identified Bilal Abdulla, an Iraqi doctor who worked at the Glasgow hospital, as the other man arrested at the airport. Staff at the Glasgow hospital said Abdulla was a diabetes specialist.