PARIS (AP) — The discovery of a huge unexploded World War II-era bomb caused transportation chaos in Paris on Friday that included the suspension of high-speed rail links with London and Brussels and the closure of a vital road artery in the French capital, hobbling France’s busiest train station, dashing travelers’ weekend getaway plans and giving commuters a major headache.

The cascade of transport woes spread from the rail to the road network, with Paris police announcing the closure of the A1 highway and sections of the capital’s always-busy ring road around the city, as bomb-disposal experts worked to make the half-ton explosive safe.

Eurostar, operator of sleek high-speed trains through the Channel Tunnel that links England with the European continent, announced the cancellation of all its services to and from its Paris hub at Gare du Nord, France’s busiest rail station, and the U.K. and Belgian capitals.

Travel plans were thrown into disarray.

“There’s no solution. We’re going to call the hotel and stay one more day. And change our train ticket,” said Michel Garrot, a retired Parisian who found himself stranded in Brussels, which he’d been visiting with his wife.

At London’s St. Pancras station, Eurostar’s London hub, travelers scrambled for alternatives. Fridays are invariably busy there with thousands of people leaving and arriving for weekend breaks. Passengers were advised to try taking trains to Lille in northern France, or fly to Paris.

“We’re looking up flights, but our options are limited,” said Lauren Romeo-Smith, part of a group that had a birthday weekend in Paris planned.

Another St. Pancras traveler, Lee Bailey, said that Eurostar had offered him a free rebooking or a refund, and an apology, but no compensation.

“I’d like to go to a Michelin (starred) restaurant in Paris on their dime, but that’s not happening, apparently,” he told Sky News.

Eurostar said that it “sincerely apologizes for the disruption and understands the inconvenience this may cause.”

At Paris’ usually humming Gare du Nord station, bright red signs warning of disruptions greeted commuters. French national rail operator SNCF says the station habitually hosts 700,000 travelers per day, making it the busiest rail hub in both France and Europe. As well as towns and cities across northern France and the Paris suburbs, the station also serves Paris’ main airport and international destinations, including London, Brussels and cities in the Netherlands.

French Transport Minister Philippe Tabarot said that the huge disruptions were caused by the discovery of a bomb that weighed half a ton. Workers found it overnight while doing earthmoving works near the tracks in the Seine-Saint-Denis region that borders Paris to the north. Bomb disposal experts were called.

Tabarot said that a “a quite large” security perimeter was set up around the bomb-disposal operation and people were evacuated. He urged commuters to postpone rail trips.

Bombs left over from World War I or World War II are regularly discovered around France, but it’s very rare to find them in such a people-packed location. The SNCF said that rail traffic was stopped at the request of police.

Sylvie Corbet in Brussels, and Jill Lawless in London, contributed to this report.