Workers in the French town of Calais—a major transit hub between England and France—blockaded the port, the Daily Mirror reported, and eventually gained access to the train terminal and entered the tracks, forcing several Eurostar trains to turn back from their destinations. The Eurostar route, which runs through a tunnel under the English Channel, was effectively shut down for most of the day.

The workers were protesting potential job cuts from the sale of two of the company's ferries to a competitor, according to the Guardian.

Early this morning the ferry company, My Ferry Link, tweeted that all services were cancelled due to industrial action.

https://twitter.com/MyFerryLink/status/613256534349455360

In the midst of the chaos, the Guardian reported that the British Foreign Office warned drivers stuck in traffic on the French side of the tunnel to lock their doors.

Following industrial action at both Calais Port and at Eurotunnel in Coquelles, cross channel services including Eurostar have been disrupted. Check the status of your booking with your operator before leaving home.

There are large numbers of illegal migrants in and around Calais, who may seek to enter the UK illegally. Although local police patrols have been reinforced, you should keep vehicle doors locked in slow moving traffic and secure your vehicle when it is left unattended.

The BBC uploaded this video of people trying to board a truck near Calais heading toward the border.

The protest ran from around 4 a.m. to 8 p.m. local time today, with hundreds of people stranded at stations in England and France throughout the day as a result. The company's apologies received a less-than-forgiving response from inconvenienced travelers: