Christopher Rodrigues, Chairman from VisitBritain:
Security is of course paramount, but it would be a tragedy if all the work being put in to showcase Britain around the Jubilee and the Olympics was undermined by a negative first impression as the world's press arrives to cover these events.
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Hundreds of passengers were ordered to leave the terminal building and flights grounded after passengers suffered difficulties breathing.
Council leaders today called on the government to provide extra money to help resettle the youngsters in the capital.
An eyewitness said: "It was very unnerving. It was just after 12pm and there were suddenly police vans and cars everywhere."