LONDON - Police say two people have been arrested in northern England in connection with the terror plots in London and Scotland.
Britain's Home Secretary Jacqui Smith has raised the terror alert level to critical, the highest possible level indicating terror attacks are imminent, in response to events in London and Scotland over the last two days.
Two men rammed a flaming sport utility vehicle into the main terminal of Glasgow airport Saturday, crashing into the glass doors at the entrance and sparking a fire, witnesses said. Police said two suspects were arrested.
The airport-Scotland's largest-was evacuated and all flights suspended, a day after British police thwarted a plot to bomb central London, discovering two cars abandoned with loads of gasoline, gas canisters and nails.
"One has to conclude ... these are linked," Dame Pauline Neville-Jones, former head of Britain's joint intelligence committee, told Sky News. "This is a very young government, and we may yet see further attacks."
Britain's prime minister, Gordon Brown, who took office only Wednesday, was being briefed on developments by his officials, Downing Street said.
In Glasgow, the green SUV barreled toward the building at full speed shortly after 3 p.m., hitting security barriers before crashing into the glass doors and exploding, witnesses said. Two men jumped out of the burning vehicle, one of them engulfed in flames, they said.
"The car came speeding past at about 30 mph. It was approaching the building quickly," said Scott Leeson, who was nearby at the time. "Then the driver swerved the car around so he could ram straight in to the door. He must have been trying to smash straight through."
Two men were arrested, Strathclyde Police spokeswoman Lisa O'Neil said.
‘Black smoke gushing out'
Passengers fled running and screaming from the busy terminal, Margaret Hughes told the British Broadcasting Corp. "There was black smoke gushing out where the car had obviously been driven into the airport," she said.
Flames and black smoke rose from the vehicle outside the main entrance. Police said it was unclear if anyone was injured. Other passengers were stranded, with at least one airplane grounded on the runway, the BBC said.
The incident also comes exactly one week before the second anniversary of the July 7 bombings that killed 52 people.
Leeson said bollards-security posts outside the entrance-stopped the driver from barreling into the bustling terminal at Glasgow's airport.
"He's trying to get through the main door frame but the bollards have stopped him from going through. If he'd got through, he'd have killed hundreds, obviously," he said.
Leeson said only the nose of the vehicle made it inside the building. Richard Grey told the BBC that the vehicle was lodged into the center of the terminal's main entrance.
‘It may have been an explosion of petrol'
"The jeep is completely on fire and it exploded not long after. It exploded at the entrance to the terminal," witness Stephen Clarkson told the BBC. "It may have been an explosion of petrol in the tank because it was not a massive explosion."
Two men-one of them engulfed in flames-were in the SUV, witnesses told BBC News executive Helen Boaden, who was at the airport at time. She described the men as South Asian.
Clarkson described him as a large South Asian man. "His whole body was on fire.... He was just talking gibberish," he told the BBC.
"An Asian guy had been pulled out of the car by two police officers he was trying to fight off and they'd got him on the floor," Grey told the BBC.
Boaden said police "wrestled him to the ground-the fire was burning through his clothes-and finally put him out with a fire extinguisher."
Lesson said an airport officials did not think the incident was an accident.
"He said the men in the car got out and started throwing petrol about-that must be how it caught fire," he said.
Another witness, Fiona Tracey, described a "bang" coming from the SUV. The vehicle was on fire and "every now and again there was a bang coming off it. ... There was definitely a bang," she told Sky News television.
Grey said the car did not explode. "There were a few pops and bangs that seemed to be the tires and the petrol."
"There was chaos at the airport," James Edgar, another witness, told Sky News. "I was in the airport building trying to book a holiday. Suddenly people were running past us. Suddenly everyone said to get out of the airport."
Glasgow airport handles around 8.5 million passengers a year, according to its website, and would have been packed with holidaymakers at the time of the incident, which took place at around 3:20 p.m. (11:20 a.m. ET), according to Glasgow police.