The MP Pamela Nash has tweeted a picture which from Portcullis House shows the scale of the Anonymous protest in Parliament Square.
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The driver stopped at the scene and the boy was taken to hospital, but he died on the way.
Sunday Times restaurant critic AA Gill has died at the age of 62, three weeks after revealing he had cancer.
The Oscar-winning actress has faced a backlash after telling a story about itching her "butt" on sacred Hawaiian rocks.