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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A 20-year-old man who died in a triple stabbing outside Parsons Green Tube station has been named by police.
David Jones was responding to London's Fire Commissioner who said the term 'fireman' was outdated and should stop being used.
A report published by the Boundary Commission for England details plans to reduce the number of MPs by scrapping 50 constituencies.