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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Goals from Charlie Austin, Dusan Tadic and James Ward-Prowse consigned Slaven Bilic's men to their fourth straight Premier League loss.
A bizarre protest against BP sponsorship at the British Museum used theatre, sea shanties and 'mermaids' to 'summon a Kraken'.
Two men have been jailed for robbing a man aged 79 as he was washing his car.