Witness Neil Walsh was waiting for a train at nearby London Bridge station when he saw the drama unfold.
The 30-year-old marketing executive from Dartford, Kent, who filmed the incident on his phone, said:
I go through there every day and always have a gawp up at the Shard to see what's happening.
I happened to notice that the window cleaning box was swinging wildly. It was quite erratic...
It was dangling from quite a thin arm and was a few feet away from the building itself, rocking left, right, up and down. It was swinging all over the place. The last few days have been windy and it must have been worse up there.
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