Thousands of Eurostar passengers delayed
Several services have been cancelled heading from London to Paris.
Thousands of Eurostar passengers are suffering severe delays and cancellations after two track fatalities and cable theft.
French media reported that 600 metres of copper cables were stolen overnight near Lille.
Eurostar said this is forcing it to run services on alternative routes, causing extended journey times.
Its services were already disrupted because many trains and staff members were out of position after two fatalities on rail lines in France on Tuesday.
The operator said it is handing out water to passengers onboard delayed trains, and has teams at stations to provide assistance.
Advice for passengers
Affected passengers are able to change their travel plans free of charge, or request a full refund.
Eurostar said in a statement: "We are deeply sorry to confirm that there were two separate fatalities on the LGV Nord high-speed line between Lille and Paris yesterday.
"Our thoughts are with the families and friends of those who lost their lives.
"The line was closed for much of the afternoon and evening, resulting in significant disruption to Eurostar services, including cancellations on routes to and from Paris.
"Trains on the London-Brussels-Amsterdam route continued to run with delays.
"This morning, disruption continues due to the knock-on impact of displaced trains and crew.
"Further to this, services have been further affected by an incident of cable theft on the same line near Lille."