The al-Qaida branch in the Arabian Peninsula is believed to be planning a terror attack during the Olympic Games in London, scheduled to begin at the end of the month. According to a report in today's Sunday Times, quoting intelligence services, the organization has recruited a Norwegian Muslim convert who was supposed to hijack a U.S. passenger plane and crash it on a suicide mission. It is not clear though that the attack targeted one of the Olympic venues, despite the timing.

Al-Qaida in the Arabian Peninsula (AQAP) has been involved in a number of attempts to carry out high-profile attacks on Western targets.

Jonathan Evans, head of MI5, Britain's domestic security service, said in a rare public address last week that "the games are not an easy target, and the fact that we have disrupted multiple terrorist plots here and abroad in recent years demonstrates that the UK as a whole is not an easy target." Despite the successes in foiling terror attacks, Evans warned that "in back rooms and in cars on the streets of this country there is no shortage of individuals talking about wanting to mount terrorist attacks here," and spoke of the threat of Western Muslim citizens who have been radicalized and trained in camps in countries such as Yemen and Sudan, traveling back to the West to carry out attacks.

According to the sources quoted in The Sunday Times, a Norwegian citizen in his mid-30s and who names himself Abu Abdulrahman converted to Islam in 2008 and has in recent months been undergoing training at AQAP bases in Yemen. There have been a number of reports over the last few months of Western citizens who joined al-Qaida and are involved in its operations in Yemen against the local Western-backed security forces.

The intelligence services believe that AQAP will try and take advantage of the fact the Norwegian has a "clean" criminal record and can travel throughout Europe with few restrictions. Around 600 thousand people are expected to be accredited to the Olympics and millions of additional tourists are expected in London over the next month. British airports are suffering from a shortage of qualified passport officers and authorities have expressed concern that the border control will be "swamped" around the Olympics and many visitors will not be sufficiently screened upon entrance.

As part of the elaborate security set-up for the Olympics, the airborne threat has also been taken into account. Anti-aircraft missile batteries have been set up in open spaces and on the roofs of apartment buildings around London, Typhoon fighter-jets have been stationed at Northolt airfield near the capital and snipers - trained to shoot down light aircraft - will operate from helicopters, taking off and landing from a battleship on the Thames. Prime Minister David Cameron will personally authorize shooting down a passenger plane believed to be on a suicide collision course. The preparations have drawn a significant amount of criticism, including from residents of one of the buildings where missiles have been stationed, and who are petitioning the court to have them removed.

Whether or not the planned attack is connected to the Olympic Games or just set to coincide with them, it is reportedly scheduled to take place during a period when western security services will be at their highest alert. The Games are also going to take place at a time when chaos in Yemen is increasing, as is the uncertainty in Saudi Arabia and the breakdown of negotiations over Iran's nuclear program.