Vaud police are appealing for witnesses to an accident on the A1 autoroute on Tuesday afternoon just after the Coppet junction, in the Geneva direction.
At around 5pm, a car driven by 62-year-old woman, veered to the right, hit the barrier and overturned.
The driver was seriously injured.
A criminal investigation has been opened to examine the exact reasons for the accident.
Anyone with any information is asked to contact Vaud cantonal police.
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