A mix of striking ferry workers and desperate migrants have caused transport chaos to travellers on both sides of the Channel.
Kent Police warned that the Port of Calais would be closed until Thursday while Eurotunnel described the situation as "grim", particularly for freight traffic.
Ferry services to and from the Port of Dover in Kent have been hit by the strike, which started at the northern French port at 2.20pm yesterday.
Striking ferry workers are blockading the French port to all users, meaning the "the local environment is in chaos ... there is gridlock", according to a Eurotunnel spokesman.
He said that in recent days the pattern of migrant activity has spread from attacking trucks on motorways to trying to access the terminal.
He said: "There are migrants everywhere which means we have to control the trucks before they get to the site.
"We are running very reduced services because we can not control traffic through to the trains quickly enough."
Crew members and catering staff on MyFerrylink services announced a strike after Eurotunnel, which owns the ships, sold the cross-channel service to rival operator DFDS.
The sale came after a competition authority ruling and left up to 600 jobs, including 70 in Dover, under threat.
MyFerrylink, which runs 16 crossings from Dover to Calais, was due to officially stop all services from a minute past midnight on Thursday. The firm could not promise that services will restart before then.
P&O Ferries chief executive Helen Deeble said: "This has left thousands of holidaymakers and lorry drivers stranded without adequate facilities - even though our employees at the port have done their level best to keep them supplied with food and water."