Security on top of building
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Small army keeps President Obama safe

Barack Obama and his wife Michelle have been the focus of attention at Buckingham Palace.

But behind the scenes wherever the president goes, so too does a small army of secret service officers, bodyguards and their high tech hardware.

They have one job - to keep the president safe.

George Alagiah reports.

  • 24 May 2011
  • From the section UK
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