PARIS — High-speed rail services between Paris and London as well as Brussels ground to halt after a power cable failure at the Gare du Nord station in the French capital on Friday, hampering the summer holiday getaway.

Eurostar warned passengers not to travel on its cross-Channel rail services to and from Paris unless it was essential, while the state controlled French rail operator SNCF said Thalys services to Brussels were also affected.

"Traffic to and from Paris is severely disrupted," Eurostar said in a statement.

An SNCF spokesman said Eurostar services would resume at 1 p.m. (1100 GMT), though delays were likely to persist. The spokesman said it was not clear what caused the outage and that there was no early indication it was due to the heatwave.

Passengers on social media described chaos at the London's St. Pancras station and the Paris terminus.

"Shambolic scenes at Ebbsfleet. No announcements...," grumbled on delayed passenger on Twitter, referring to a station east of London.

Another tweeted: "I’m on a #Eurostar train heading to Paris. It was held for a while but now we seem to be traveling fast toward Paris again. It isn’t clear if Gare Du Nord will be open to arrivals." — Reuters