The backgrounds of up to 500,000 people are being scrutinised in an unprecedented security screening designed to stop the Olympic Games being disrupted by criminals or terrorists, the Guardian has learned.
In what is understood to be the biggest vetting process since the second world war, the Home Office has so far refused about 100 applications for Games accreditation, mostly because of concerns about the extent of people's criminal records.
However, some people have been denied accreditation on the advice of MI5, which has to assess whether a person might pose a significant threat to national security.
The 500,000 figure includes anyone seeking employment at the Games, as well as athletes, coaches and officials from more than 200 competing nations.
The Guardian has been told the threshold for refusing accreditation has been set high, which means some of those working at the Olympics this summer will have "come to the notice of" the police or MI5 in the past.
"To be rejected, they have to pose a significant potential threat to the safety of the Games," said a source. "They won't be rejected on the basis that information is held about them.
"A judgment has to be made, not on the basis that there is an official record, but does this person pose a significant threat to security."
Police and MI5 have been taking a careful look at all those who may end up working at the Olympic sites. It is an obvious way for would-be terrorists to gain access to venues, and police are aware that terrorists may masquerade as casual workers looking for temporary jobs.
However, those involved in the security of the Games say they have found no evidence so far that al-Qaida sympathisers have tried to infiltrate the civilian workforce.
The vetting process began in earnest last October and officials are more than two-thirds of the way through the process, which is expected to be completed in the coming weeks.
It has been one of the core tasks of counter-terrorism officials but the scale of the operation, and the depth of the checks required, has made it a drawn-out affair.
Among those still to be vetted are many of the 10,000 security guards who will be employed by G4S, the private firm which is contributing 23,700 personnel at the Olympic venues.
A big recruitment drive was launched by G4S when the number of guards it was expected to provide grew from 2,000 to 10,000, after it emerged that the Games organisers, Locog, had seriously underestimated the number required. The 70,000 volunteers recruited by Locog, who are considered crucial to the success of the Games, are also being screened.
Home Office officials said that many of the 10,500 athletes taking part in the Games and those accompanying them were used to travelling to international events and were unlikely to pose any security problems.
There remain outstanding questions surrounding a handful of high-profile individuals, including members of the Syrian Olympic committee with close links to the Assad regime.
It is believed that discussions are continuing over whether to bar General Mofwaq Joumaa, the president of the Syrian national Olympic committee, from entering the UK.
Scotland Yard and MI5 are understood to have hundreds of investigations "live", with the Olympic security operation likely to reach a new pitch as teams arrive for training before the event.
It is understood that the security service has not set up a separate Olympic security unit, believing it would be wrong to draw a distinction between terrorism and Olympic terrorism.
The security service is said to be bracing for a possible deluge of intelligence from foreign police forces and intelligence agencies, who will not want to sit on any information just in case it reveals a potential threat to the Games. MI5 remains confident it will be able to cope, and the Home Office said it will leave nothing to chance when it comes to security.
"We are undertaking stringent checks on all those seeking accreditation," a Home Office spokesman said. "This rigorous process has been designed to ensure those working at the Games are fit to do so. We will leave nothing to chance in our aim to deliver a safe and secure Games that London, the UK and the whole world will enjoy."
-Nick Hopkins, Owen Gibson and Sandra Laville
Source: www.guardian.co.tt
When London organised the Olympic Games for the first time in 1908 they had less than two years to get ready. So they needed a man of the calibre of Lord Coe to head the Organising Committee. They found one in William Henry Grenfell (pictured below), later Lord Desborough of Taplow.
"She pretended to be terribly angry with me and demanded to know why I had tried to make her a widow," he replied.
He galvanised the locals into subscribing for a town clock. It was eventually unveiled by his wife and can still be seen today. He also put in train the provision for electric light to the town.
At the time, Desborough was leading a British fencing team (pictured above, second right) to the 1906 Olympic Games in Athens - a tenth anniversary celebration of the modern Olympic movement. Although already 50, he was still very competitive on the piste.
By now an IOC (International Olympic Committee) member, he became chairman of an influential Organising Committee and negotiated a favourable deal with the organisers of the Franco Britannic Exhibition, due to take place at Shepherd's Bush in the summer of 1908. They agreed to build the Stadium (pictured above) to the specifications of, and at no cost to, the Organising Committee. This they did in return for a generous proportion of the gate receipts, but it should be said that these were a real unknown quantity. There was no great rush for tickets at the 1908 Games.
"We felt that in the country which may almost be called the motherland of athletics and sport, every effort should be made to make the games worthy of the occasion and of the place where they were held," he said.
The 1908 Olympic Games began in April, but the main events were not until July and these came at the Great - and free - Stadium itself. There was a grand parade of teams, and Desborough himself invited King Edward VII to perform the opening.
The Italian received a cup from Queen Alexandra (pictured below), joined for the presentation ceremonies by Lady Desborough. The picture of Dorando approaching the line remains one of the great images in Olympic history. Such events really put the Olympic Games on the map.
Within a few years, Desborough was hit by family tragedy. His sons Julian and Billy were among the millions who perished in World War One. His personal loss makes his words, written at the time of the 1908 Games, seem all the more poignant. "These young men are also representative of the generation into whose hands, the destinies of most of the nations of the world are passing at this moment, and we may hope that their meeting thus periodically, the enthusiasm which they share may have a beneficent effect hereafter on the cause of international peace."
Usain Bolt today helped Bob Marley's daughter launch Jamaica's team uniform for London 2012. 
The collection, launched a special ceremony in London hosted by British DJ Trevor Nelson, incorporates high-tech fabrics and silhouettes engineered to enhance the performance of the athletes hailing from the fastest country in the world.
Germany are set to send their smallest team to an Olympics since reunification and expect to finish below Britain in the medal table at London 2012, they have admitted at a press conference in Frankfurt attended by Sebastian Coe. 
Coe, a close friend of Bach's, the vice-president of the International Olympic Committee (IOC) who is expected to succeed Jacques Rogge as President next year, promised a great London 2012.
June 4 - The London 2012 Olympic Torch Relay has been disrupted for the first time on its 70-day tour of the UK following a dissident Republican protest in Northern Ireland.
"Due to a protest that took place at the rear of the Guildhall this afternoon, the Torch was diverted past Guildhall Street on to Whittaker Street where it continued on to the peace bridge," she said.