Sports fans will face airport-style security at the 2012 Olympic Games say police, as they start testing London's venues against potential terror threats.

London 2012 Olympic Games basketball court: police begin terror tests (Image: Getty)

The 34 Olympic venues, surrounding street parties and public events will be policed at a "severe threat level" - the second highest status - in Britain's biggest peacetime security operation.

The Home Secretary, Theresa May, said all key Olympic organisations and Government departments face a series of at least 10 stress tests to ensure they are prepared.

The country faces several potential terror threats, from al-Qaeda to dissident Irish nationalists.

The 2012 Games also coincide with the 40th anniversary of the Munich Olympics, when 11 Israeli team members died after being held hostage by Palestinian gunmen.

The stress tests will analyse how the departments work together, how they work with London 2012 organisers and how information is shared with the public.

Testing is already underway and has so far focused on the main stadium and the velodrome at the Olympic Park in Stratford.

Police have been testing their bomb-searching speeds and learning the geography of the venues.

A counter-terrorism exercise involving the Ministry of Defence and other emergency services took place in the Olympic Village in May.

"I am trying to ensure that we produce 34 venues that are secure, that people can go in and have a really good time, that people can feel safe inside and their focus can be on the sport," said the Metropolitan Police Assistant Commissioner Chris Allison, who is also the Olympic security coordinator at Scotland Yard.

Naval tactics for the Thames

Sports fans will face 20-minute queues during peak times as they are subjected to airport-style security checks, he said.

Mr Allison has also talked of using Royal Navy tactics in policing the city’s waterways, and employing specialists from other police forces such as firearm officers, and protection and search officers.

I am trying to ensure that we produce 34 venues that are secure, that people can go in and have a really good time. Met Police Asst Commissioner Chris Allison

Most of the 12,000 police will be unarmed, but there will be armed police present in some venues.

Proposals for video surveillance planes and jets on standby for any potential airborne terrorist threat are still being discussed.

Police helicopters will be used and a secure tetra radio network will be in place, while a significant number of CCTV cameras will be installed at the Olympic Park.

At a briefing at Scotland Yard, Britain's top police officer, the Metropolitan Police Commissioner Sir Paul Stephenson, said that while he was delighted with intra-agency progress on security preparations he was not complacent.

"I want to stress that the summer of 2012, for the Metropolitan Police and indeed the nation and the Government, isn't just about the Games... The challenge for the Met in particular is to continue to run policing services here in London. And we are going to do that," he told reporters.

The Home Secretary, who also attended the briefing, said the Government had set aside a budget of £600m for policing the Games but that it was on course to come in under budget at around £500m.