Eurostar is investigating one of its services between London and Paris which took almost ten hours.

A "series of technical incidents" was blamed for the delay to the journey, which normally takes just over two hours.

The service was expected to leave London at 20.05 GMT on Friday, and arrive at the Gare du Nord in Paris at 23.36 French time - two hours and 31 minutes later.

But the 643 passengers finally arrived in Paris at 9.10 on Saturday morning, following an "exceptional series of incidents".

The passengers had to change trains twice during the journey due to mechanical faults.

A Eurostar spokesman acknowledged that the passengers had been though a "completely unacceptable experience" and confirmed that an internal investigation was underway.

He said: "Eurostar and SNCF have launched an immediate internal investigation into an exceptional series of technical incidents that took place during the journey.

"We apologise profusely to our travellers for the unacceptable delay, inconvenience and frustration that they have suffered."

He added: "We are offering everyone on board a full cash refund on both legs of their return tickets and in addition a free return ticket for future use."

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