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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Five teenagers have been arrested in connection with the murder of a Polish man in what police say is a possible hate crime.
A man who fell asleep with a loaded gun on his lap while sat in traffic has been jailed.
A comedian who fell asleep in an Uber car got a shock when the journey that should have taken minutes ended up as a 35-mile detour.