Speaking to the Evening Standard, Chief Superintendent Mick Johnson, who was the match commander, said: "Picking them out is one of the difficulties we face in terms of taking this forward. The chap who was arrested shouted in an officer's face, so it was fairly easy.
"Another man stood on his own and started singing the 'Y' word, so he was approached and warned and took on board what the officer said. The plan was quite straightforward."
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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.