London mayor Boris Johnson told ITV News that he was "absolutely confident" that people responsible for the death of solider Lee Rigby in Woolwich would be brought to justice.
He said: "People in London should realise that this is a very safe city and they can go about their business as normal."
"The killers of Lee Rigby are going to be brought to justice - I can be absolutely confident of that," he added.
He said he had no concerns about the time it took police to arrive to the incident and paid tribute to Ingrid Loyau-Kennett, a woman who confronted the alleged attackers as a man lay dead in front of them.
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