Eurotunnel customers faced hours of delays on Tuesday after refugees rushed the terminal in the French region of Calais in a desperate bid to break through security.
Waiting time for passenger services in Folkestone was about two hours while the delay in Calais was about three hours. Eurotunnel said it was unable to sell tickets to passengers without reservations at either end, The Guardian reported.
Eurotunnel has suffered disruption to its services throughout and now faces new tactics from refugees and migrants, whose numbers have swelled to 6,000 in the makeshift camps outside Calais, known as the Jungle.
Eurotunnel said hundreds of refugees had tried to breach the 20-mile perimeter in recent days, in diversionary tactics.
These large groups draw police and security personnel away from sensitive access points - roads and tracks near the terminal - that smaller groups then try to breach.
At least 15 people have died in or near the tunnel since the start of the cross-Channel migrant crisis.
One person died last week after being hit by a freight train at the Channel tunnel's Coquelles terminal.
In August, Eurotunnel said the number of attempts by migrants trying to get into its terminal near Calais had fallen to about 150 a night, down from a high of 2,000 in the previous month.
Extra security, including fencing, paid for by Britain, has been put in place, aimed at making it harder for migrants to get onto the platforms and trains.
