Judge, David Radford warned Mary Konye that she will face jail when he sentences her on March 7:
I should make clear that, in my judgment, this is a case that will, in all likelihood, need a substantial custodial sentence. It is inevitable, but it won't be dealt with until I have received those reports.
Victim, Naomi Oni burst into tears as she left the courtroom and was hugged by family and friends.
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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.