Passengers at Heathrow and Gatwick are facing long queues at passport control because of a fault with UK Border Force computers.
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A new mansion on The Bishops Avenue in Hampstead has been bought for £33.7m.
London's mayor has launched a campaign to inform Londoners about tips to cope with air pollution.
Three-quarters of Londoners think their area is undergoing a housing crisis, according to a poll from the Chartered Institute of Housing.