Jenny Reeves (@Jennyflyer1) was one of the first to post a picture on Twitter.
And Transport for London sounded the all-clear after the "invasion" had been averted.
The filming of Doctor Who has finished at Westminster Bridge, the Daleks are in the process of being removed.
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Mayor of Newham Sir Robin Wales criticised the International Olympic Committee on the fourth anniversary of the opening ceremony.
If you're missing the euphoria of London 2012 here's your chance to own a real piece of Olympic history.
Her owners were convinced she was gone for good and were shocked when a Parisian cat rescue centre got in touch.