Peter Hendy, the Transport for London Commissioner, has said Crossrail 2 is needed because London's population is growing by "a tube train a week".
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The installation is the first in London by acclaimed British underwater sculptor Jason deCaires Taylor, part of the Thames festival.
Services through Kempton Park were suspended over the weekend due to an "obstruction on the line".
A leading sexual health clinic has apologised after mistakenly sharing the HIV positive status of hundreds of patients in an email.