"This was abrazen robbery, and appears to have been well planned and thought through.Fortunately no one was injured. The store was very busy and this will have beena shocking thing for people to witness.
"I'd like to thank those members of the public who stepped in and detainedour two suspects. Their quick thinking and brave actions have helped ourinvestigation."
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The former London Mayor also claimed Tony Blair's decision to ignore security advice had "killed 52 Londoners".
The victim, a woman in her 40s from Hillingdon, west Londion, was conned into handing over the fortune to a man who faked his name.
Inspectors found a culture of bullying and major problems with poor ambulance response times at the trust, which is the biggest in the UK.