Astonishing before and after pictures show the scale of the collapsed bridge that was supposed to eventually carry a dual carriageway over the Manchester Ship canal.
Witnesses reported hearing a loud bang and said it felt as if there was an “earthquake” in the area.
It appears a concrete platform being constructed between four 31-metre (93ft) high pillars fell to the ground on Monday morning.
The structure is part of a new lifting bridge which will carry a new dual carriageway over the Manchester Ship Canal, joining the Trafford Centre on one side to Salford.
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