On 29 June 2007, two unexploded car bombs were discovered in London. The first device was found in a car parked near the Tiger Tiger nightclub in Haymarket and two large gas canisters and a large number of nails were found in the car. The second device was left in a blue Mercedes-Benz saloon in nearby Cockspur Street, but was not discovered until after the car had been towed away as it was found to be illegally parked.
On 30 June 2007 a dark green Jeep Cherokee, registration number L808 RDT, was driven into the glass doors of the main terminal of Glasgow International Airport, and burst into flames. A suspected car bomb failed to detonate, and the driver of the car, Kafeel Ahmed, on fire after allegedly dousing himself in fuel, together with a second suspect Bilal Abdullah, accused of being the Jeep's passenger, attacked the police. Fire extinguishers were used to put Ahmed out, and he was subsequently tackled by two police officers and bystanders. Abdullah was subsequently convicted of conspiracy to murder, and sentenced to life imprisonment 30 June – during the evening, Liverpool John Lennon Airport was closed for eight hours, whilst a vehicle was removed and taken away for forensic testing, reopening at about 04:40 on Sunday morning.
3 July – due to a suspect package being discovered, around midday Heathrow Terminal 4 was closed until the early evening.
On 30 June, ABC News reported that United States law enforcement officials were informed two weeks prior to the Glasgow incident of possible attacks on "airport infrastructure or aircraft" in Glasgow leading to the placement of Federal Air Marshals on flights into and out of Glasgow.
On 4 July, The Times reported that an al-Qaeda leader in Iraq boasted, to Canon Andrew White, before the failed bombing, that his group was planning to attack British targets and that "those who cure you will kill you". White passed this information onto the British government, but without the specific wording, in mid-April 2007.
The UK Government blamed the events on al-Qaida and the two incidents were linked, by police, to the same two men.
By 3 July eight people, aged between 25 and 27, had been arrested. One of those arrests was made in Australia, the rest in the United Kingdom. All but Kafeel Ahmed, the Glasgow driver, have links with the National Health Service; six are believed to be doctors or medical students while the wife of one of those arrested formerly worked as a laboratory technician. Kafeel Ahmed applied, unsuccessfully, several times to the Australian Medical Association for certification in Western Australia.
Those arrested were:
- Dr. Kafeel Ahmed, aka Khalid Ahmed, born in India, driver of the Glasgow car. Taken to hospital after the attack for treatment of burns over 90% of his body surface, he died on 2 August 2007.
- Dr. Bilal Abdullah, 27, from Iraq. Passenger in the car, he was arrested immediately at Glasgow International Airport. Convicted of conspiracy to murder and sentenced to life imprisonment with a requirement that he spend at least 32 years in jail.
- Dr. Sabeel Ahmed, 26, born in India and brother of Kafeel (above), a doctor at Halton Hospital in Cheshire. Sentenced to 18 months imprisonment in London for withholding information he was released on time served (270 days) and deported.
- Dr. Mohammed Asha, 26, from Jordan, a neurologist. Arrested on the M6 motorway. Acquitted of conspiracy and successfully fought deportation from the UK.
- Marwah Dana Asha, 27, from Jordan. Wife of Mohammed Asha and arrested with him on the M6 motorway. She was later released without charge.
- Dr. Muhamed Haneef, 27, from India and working in Australia. Distantly related and with some contact to the Ahmed brothers he was wrongly accused by the Australian police of a link to the bombing and held for 13 days without charge. In 2008, Haneef's lawyers tried and failed to get documents pertaining to the case released in Australia.
- An unnamed 28-year-old Saudi man, arrested in Houston, Renfrewshire. Reported to be a medical student working at Royal Alexandra Hospital. Released without charge on 15 July.
- An unnamed 25-year-old Saudi man, arrested in Houston along with unnamed 28-year-old. Also reported to be a medical student at the RAH. Released without charge on 15 July.
These attempts resulted, on 30 June, in the threat level in the UK being raised to 'critical', the highest of five possible levels, meaning a terrorist attack was expected imminently. The raising of the threat threshold effectively put Britain on par with Iran, Guatemala, Jordan, Rwanda and Uzbekistan in terms of the potential threat posed. However, on 4 July the threat level was reduced to 'severe' but that still meant that an attack was highly likely.
In July 2007, the visibility of policing was markedly increased, for example patrols were bolstered at Canary Wharf, home to some of the world's largest banks, police were ordered to step up 'stop and searches', and there were armed police at airports and railway stations. Further, cars have been banned from approaching airport terminals and are instead directed to outlying car parks and passengers bussed in.
On 1 July, U.N. Secretary-General Ban Ki-moon deplored the terrorist attack on Glasgow's airport and the foiled car bomb plot in London.
Also on 1 July, Michael Chertoff, United States Secretary of Homeland Security, announced that the United States alert levels would remain unchanged at orange for airports (the second highest), and at yellow nationally (the third highest).
Concerns have been expressed that al-Qaeda might use Caucasian operatives in the future and that they are planning to infiltrate the security services.
A decision has been made to equip major UK airports with a 'virtual tripwire', a technology known as 'Video Analytics', the use of computers to monitor CCTV images that allows the computers to automatically summon the security authorities if pre-determined situations are detected.
Increased vetting of medical staff has been put in place as a result of these incidents. Around 90,000 of the doctors in the UK trained overseas, 2,000 of them from Iraq.