Britain in Frenzy After Terror Attack

U.K. travel was in a frenzy today with underground and airline terminal closings in the aftermath of the latest terrorist attack at Scotland's Glasgow airport and two failed car-bomb attacks that were discovered in London's West End.

At least three major security alerts in London were reported today and two more arrests were made under the terrorism act, though it's not yet clear whether the arrests are linked to a terror plot apparently organized by eight medical professionals.

Also on Tuesday, attackers rammed a car into an Asian-owned shop in the Glasgow suburb of Riddrie and set it ablaze. Residents fear it was revenge for the airport strike, Reuters reported. Police are investigating.

The BBC said that all the suspects are believed to be medical professionals who have worked for the British National Health Service. Eight suspects have been arrested so far in connection with the attack in Glasgow and failed car bombs in London and Glasgow.

All planes at Terminal 4 of Heathrow, London's largest airport, were grounded after police investigated a potential terror threat. An ABC News reporter at the scene said all passengers and airline staff were asked to disembark from their planes and completely evacuate the terminal. Passengers were told that due to the presence of "suspicious passengers," everyone in the terminal had to go through an additional security clearance. Police brought in sniffer dogs to investigate.

In London, explosives experts performed a controlled explosion on three fire extinguishers left on a pavement outside Hammersmith Tube station. A United Colors of Benetton store was shut down because of the alert.

The store manager, who identified herself as Pilar, said: "I wasn't scared. I did not even have time to think. Obviously it's inconvenient. We had to close the store for an hour, and it will affect business, but these threats are something we have to take seriously." She said she was satisfied with the conduct of the police.

Yet another incident was reported near a busy market and transport hub in Sheperd's Bush, London. Police and emergency services quickly arrived at the scene to investigate the situation. Police declared the area safe within an hour.

In Glasgow, three controlled explosions were carried out on a suspicious car parked outside the Forth Street Mosque. The mosque is located in a part of Glasgow with a large Asian population.

The United Kingdom is currently at a critical terror alert, which means that a terror attack is thought to be imminent. Authorities are asking civilians to be vigilant. Traffic in the usually crowded London streets is now almost impassable because of security measures. There is added police presence on the London subways, where a deadly attack occurred on July 7, 2005.

Authorities urged travelers to the airport to abandon cars in favor of public transportation, but they are not asking the public for further help with the terror plot investigation. It appears that in the London-Glasgow terror probe, there have been no public appeals to trace specific individuals. It seems that investigators have a wealth of information, clues, evidence and leads from at least 19 different scenes.

Dan Frugtniet, a 32-year-old sales manager who also works in the Hammersmith area, said he found the reaction of the authorities to be "scare-mongering" and "manipulative." His friend Tom Prince, a 28-year-old project manager, disagreed and said "it's not the police who are at fault, it's the public" because "people are overly vigilant and they phone in about everything" and the police are compelled to look into every alert.

Arrest Made in Australia After Call

The investigation is spanning the globe, with the latest arrest being made in Brisbane, Australia. A man of Indian origin, Dr. Mohammed Haneef, 27, is believed to have qualified in Bangalore, India, in 2002. He was arrested at Brisbane Airport; authorities believe he intended to travel with a one-way ticket to India on Monday.

Haneef was working at Gold Coast Hospital in Queensland, Australia, but had previously worked at Halton Hospital, Liverpool. According to Reuters, Australian Prime Minister John Howard said that no official charges had yet been filed against Haneef. Australian media are reporting that Haneef was arrested after a phone call was made to him from one of the suspects arrested in London.

Another suspect who has yet to be named by authorities was arrested in the Lime Street area, Liverpool, late Saturday. ABC News has confirmed that the suspect worked at the same hospital as Haneef and was also a doctor.

Two suspects were arrested in Glasgow, after they drove a fuel-laden car bomb into Glasgow airport. Police in Scotland confirmed that the Glasgow airport attack was connected to the two failed car bombs found a day earlier in London's West End. One suspect Dr. Bilal Abdullah is believed to be an Iraqi national. Another man who has yet to be identified by authorities is being treated for burns in Glasgow. Both men have been transferred by Scottish authorities to London Metropolitan Police.

Cell phones are thought to have played an integral part in the investigation because police found two handsets in the failed car bombs. The cell phones were rigged to detonate the bombs. Numbers found in the cell phones were then used by authorities to help round up the suspects.

Suspects arrested in the United Kingdom are being held in London's high-security prison Paddington Green.

The BBC also reports that Dr. Mohammed Asha, 26, who studied medicine in Amman, Jordan, in 2004, was arrested in England in connection with the investigation. Authorities also said that his wife, Marwah Dana Asha, 27, had been arrested, the BBC said.

Two more suspects, ages 28 and 25, were also arrested in Paisley near Glasgow. Both the men are believed to be of Saudi origin.

The British head of counterterrorism, Chief Peter Clarke, called this a fast-moving investigation with new information coming to light "hour by hour."

Ammu Kannampilly contributed to this report