calais
A police vehicle drives past lorries are backed up on the M20 motorway which leads from London to the Channel Tunnel terminal at Ashford and the Ferry Terminal at Dover, June 23, 2015. The Channel Tunnel terminal and ferry port at Calais were both shut after industrial action by workers leading to all cross-Channel travel being stopped. Reuters/Peter Nicholls

Transportation services began to resume Wednesday at the French hub of Calais after a major wildcat strike by ferry workers threw travel between France and the U.K. into chaos. The strike ended Tuesday.

Both the ferry and the Eurostar train services are running again though roads in Kent -- on the British side -- remained backed up, the Guardian reported. Beginning Tuesday, French workers protesting plans to sell two of the ferries to a rival firm, burned tires and barrels, and blockaded the port and rail line, prompting all passenger and freight services across the channel to be canceled.

"It is hugely regrettable that we've seen these incidents occurring as a result of industrial action in France,” U.K. immigration minister James Brokenshire told the BBC, adding that the U.K. was sending “additional resourcing into the port of Dover to enhance screenings and detections there so that we’re looking at this on both sides of the Channel.”

Riot police moved in to clear off the workers who blocked the Channel Tunnel tracks with tear gas. Drivers and truckers who were using the Eurotunnel service were delayed for hours, leaving hundreds of freight trucks still parked along the M20 motorway.

The strike was also exploited by hundreds of desperate refugees who tried to board trucks bound for the U.K. in the chaos on Tuesday. Around 3,000 migrants are thought to be living in the area around Calais, awaiting their chance to cross the border into the U.K. Footage from the scene showed migrants running to open the doors of slow-moving trucks.

An advisory was issued calling on all truck drivers to keep their doors padlocked, stay close to each other and avoid stopping within 60 miles of the port. Border security has also been increased on both sides of the Channel.

Aid workers had warned last week that conditions in the Jungle 2 migrant camp were growing increasingly desperate, with shortages of food and shelter causing migrants to take greater risks in their efforts to enter the U.K.

The U.K. Home Office reportedly estimates that around 19,000 people have attempted to illegally cross the channel from France to Britain in 2015, about double the number for the same period last year.

The issue of migrants has been a significant point of diplomatic contention between Britain and France. Calais Mayor Philippe Mignonet told the BBC that the British government was to blame for the number of people seeking to board the trucks. “We will block the port – as simple as that. We’ll arrange to block the tunnel if nothing is done,” he reportedly said.

The Home Office said that it was coordinating "with its French counterparts to strengthen the security of the border," according to the BBC, and that it would “bolster the security and infrastructure of ports in Northern France and Belgium.”