Nick Christoforou, who was a passenger in the Uber car, along with his colleague Sophia Toon, said that their Uber driver drove the Citroen DS5 vehicle off the end of a jetty in Port Pierre Canto, Cannes (Provence-Alpes-Côte d'Azur), during their early-morning ride.
Mr Christoforou - who is from London - said that everyone in the car would have been “100% dead” if he had not managed to get a car door open and swim to the surface, before ensuring everyone else had been able to escape too.
The car had “sunk slowly” into a three-metre deep area of water, local police said, allowing the passengers to swim free.
The driver was breathalysed at the scene and found to be sober, reports said; although he no longer works for Uber.
However, Mr Christoforou said he and his colleague were still charged the €20 fee for the trip, and only later managed to get a refund, along with compensation.
A statement from Uber read: “We were shocked to hear about this terrible accident and are grateful that everyone in the vehicle is safe.
"Following the report, we contacted both passengers to ensure that they were OK and continue to offer counselling services and support while they await the outcome of their claim against the driver’s insurance.
"The licensed driver involved is no longer able to use the Uber app."
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