Speaking to the Evening Standard, commuter David Banks said: "There were just a lot of police around, police vans and cars and officers around a skip. The skip was between one of the exits to the railway station and car park itself."
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Surrey Police are appealing for witnesses after the driver was seriously injured in the crash in the early hours of Saturday.
The Duchess of Cambridge has been driven to St Mary's Hospital in London in the "early stages of labour", Kensington Palace has said.