Molly Solomons from UK Uncut gives the reasons why the group decided to stage a street party outside the Deputy Prime Minister's home.
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George Osborne told MPs London would shoulder a large part of his 37% reduction in transport funding.
The prison was originally opened in 1852 as a mixed prison before becoming the first female-only local prison in England in 1902.
The victim was travelling between Seven Sisters and Highbury and Islington when she was assaulted.