LONDON, ENGLAND - MAY 03: Police officers with automatic weapons guard Downing Street on May 3, 2011 in London, England. The Government has warned the public to be vigilant for terror threats in the ... more 
LONDON, ENGLAND - MAY 03: Police officers with automatic weapons guard Downing Street on May 3, 2011 in London, England. The Government has warned the public to be vigilant for terror threats in the wake of the killing of fugitive terrorist Osama Bin Laden by US special forces in the Pakistani city of Abbottabad. The current UK threat level from international terrorism which is set by the Home Office is "Severe", meaning that a terrorist attack is highly likely. (Photo by Oli Scarff/Getty Images) less 
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Getty Images | Photo By Oli Scarff / Getty Images
Tue, May 3, 2011 10:34 AM EDT