Fresh disruption was brought to Channel tunnel services after about 150 migrants tried to storm the terminal in Calais in a bid to board UK-bound freight, reports The Guardian.
Eurotunnel said services were delayed and cancelled after migrants attempted to access restricted areas on the French side.
The incident caused a return of queues on the M20 in Kent for lorry drivers trying to cross the Channel after Kent police reintroduced Operation Stack.
It also prompted renewed calls for authorities to act to solve the worsening Calais migrant crisis, which is costing the UK economy millions of pounds.
The Fresh Produce Consortium estimates that £10m of fresh fruit and vegetables have been thrown away since the start of the year as a result of the problems.
A Eurotunnel spokesman said the incident was affecting freight traffic only, with passenger services running to a full timetable.
He said: “Eurotunnel reiterates its call to the authorities to provide a solution to the migrant crisis and restore order to the Calais region.”
The Port of Dover, which faced heavy disruption this week due to striking ferry workers in France, said it remained “open for business”.
A port spokesman said P&O Ferries was operating a full Dover-Calais service, while DFDS Seaways was running full services to Dunkirk.