Chancellor George Osborne and London Mayor Boris Johnson were at a former gasworks which has been deserted for 40 years to launch the scheme. They say the site in Tottenham can now be built on after they removed planning restrictions to get more homes built quickly.
Fifty thousand new homes will be built, 40% of which will be affordable, housing 250,000 people.
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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."