European rail operator Eurostar is investigating yet another in a long series of cross-channel train breakdowns, which left over 700 passengers in darkness.

The service, which operates from London to Paris, came to a grinding halt with its lights off just south of Ashford in Kent at about 10:45pm last night after what the operator described as a major technical malfunction.

740 passengers were forced to climb down the ladders and onto the tracks and then back up onto a replacement train that arrived over an hour later.

Eurostar, which has been heavily criticised over a string of pre-Christmas breakdowns that left thousands of passengers stranded overnight in the tunnel, apologised for the latest stoppage and said that a full inquiry was under way.

A spokeswoman for Eurostar said that they didn’t know exactly what caused the stoppage, but the matter was being fully investigated.

She went on to apologise for the passengers for any inconvenience caused.

Passengers reported experiencing hot temperatures on board the stranded trains, along with broken toilets and staff struggling to locate emergency lighting.

A British passenger said that just after 10 minutes after departing Ashford, the train stopped, at which point the power went out and the passengers were left in darkness.

The rescue train arrived at St Pancras just after 2:30am, over four and a half hours later than the scheduled arrival time.