International high-speed rail service Eurostar, which connects Brussels and London, canceled all services Tuesday because of technical problems in the Channel Tunnel.

“Due to a problem with the overhead power supply and a subsequent failed Le Shuttle train the Channel Tunnel is currently closed. Unfortunately, this means we have no choice but to suspend all services today until further notice,” the company said in a service update on its website.

Le Shuttle, the rail service that transports vehicles and passengers through the Channel Tunnel, is experiencing delays of up to three-and-a-half hours, according to an update on its website.

Eurostar also urged passengers not to travel to stations, which include Brussels-Midi, Gare du Nord in Paris and St Pancras in London.

British media reported there were traffic jams in front of the tunnel terminal in Folkestone, England and stations crowded with stranded passengers in London and Paris.

Eurostar denied reports about stranded train passengers in the tunnel. “It is a broken shuttle (LeShuttle) that has now been moved out of the tunnel,” a spokesperson told POLITICO.

The Channel Tunnel links Great Britain with mainland Europe. Under normal conditions, the journey from London St Pancras to Brussels-Midi takes about two hours.