London: British police have begun testing Olympic venues against all potential terrorist threat, including from Irish dissidents and Islamists, the policeman in charge of 2012 security.
Next summer`s London Games are predicted to be Britain`s biggest peacetime security operation, and will be policed at severe threat level, the second-highest status.
The country faces a number of potential threats, one of the most high-profile being from al-Qaeda after Britain`s support of U.S. military operations in Afghanistan and Iraq, while dissident Irish nationalists pose a renewed challenge.
The London Games also coincide with the 40th anniversary of the Munich Olympics, when 11 Israeli team members died after being held hostage by Palestinian gunmen.
"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," Metropolitan Police Assistant Commissioner Chris Allison, Olympic security coordinator, said from his office at Scotland Yard.
"That is at the heart of all our planning, and we`ll do everything that we need around the outside to ensure that happens."
As well as the 34 venues, police will also have to make sure street parties and public events in the city`s parks go ahead without disruption.
Testing has so far focused on the main stadium and velodrome at the Olympic Park in Stratford, east London, where police have been working with the London organising committee (LOCOG), responsible for screening spectators.
Police tested their defensive search procedures, for example seeing how long it would take to look for hidden bombs, and improving their understanding of the venues.
A counter-terrorism exercise involving the Ministry of Defence and other emergency services took place in the Olympic Village in May.
The police will prepare for all possible scenarios covering all venues and aspects of security, up to and throughout the Games, Allison said.
He said Munich would be a factor in the preparations, but it was looking at all possible terrorist-related activity.
"You cannot think about the Olympics without taking that into consideration, without thinking about that," he said.
"Clearly we have to look at every terrorist threat that there is out there and make sure we have got the appropriate mitigations in place."
Britain is currently operating on a severe threat level, meaning a militant attack is considered highly likely.
London has been a victim of militants in the recent past. In July 2005, four young British Islamists carried out suicide bomb attacks killing 52 commuters on the capital`s transport network, a day after the city was awarded the Games.
Northern Ireland has seen an upsurge in shootings and bombings targeting police officers and soldiers during the past two years by nationalist splinter groups who want to end British rule.
While last Friday, Libyan leader Muammar Gaddafi said Libyan fighters would descend on Europe "like a swarm of locusts or bees", if NATO did not halt its bombing campaign.
Sports fans will face airport-style security before being allowed into venues, with queuing taking between 15 and 20 minutes during peak times, he said.
Allison has talked about drawing on certain niche Royal navy skills to help police the city`s waterways, and using specialists from other police forces such as firearm officers, and protection and search officers.
Armed police would be deployed in certain circumstances, but the majority of the 12,000 officers would be unarmed.
Reports of video surveillance planes being used and jets placed 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.