Police have also taken the unusual step of naming 22-year-old Jamie Marsh-Smith who they want to speak to in connection with the murder. He is known to have links to Tottenham, Hackney, Camden and Kilburn.
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A police officer who spent six days crawling the London Marathon in a gorilla costume has finally completed the 26-mile route.
The victim of a "violent and sustained attack" on the top deck of a London bus has been named as Archie Sheppard.
Transport for London has made the badges and accompanying cards permanently available after a successful trial in autumn last year.