The number of freight trains using the Channel Tunnel fell by a third in the last three months as the migrant crisis gripped Eurotunnel.

Commercial traffic slumped 33% in the third quarter of this year as many services were suspended due to disruption in Calais.

However total like-for-like revenues for Eurotunnel still increased 3% to €334.4 million (£244.2m) compared to the same period last year.

Shuttle revenues increased by 3% to €172 million (£125.6m) while passenger and truck traffic remained broadly stable, both down 1%, despite disruption caused by the camp of about 6,000 migrants in France.

Rail freight tonnage has fallen by 27% to 283,016 as the number of freight trains using the route fell to 459 from 681.

The company has put up nearly 18 miles of high security fences around the entrance to the tunnel at Coquelles, while security personnel have been doubled to nearly 250 people, including dog teams.

Despite the disruptions, its Le Shuttle service set new records this summer with almost 658,000 passenger vehicles crossing in July and August.

Its all-time record for traffic carried in one day was broken on August 15, with 17,000 vehicles transported.

For the first nine months of the year, revenues for the group reached €931.1 million (£681.4m), up 6%, although this excludes Dover to Calais service MyFerryLink, which it was forced to close in July.

Chairman and chief executive Jacques Gounon said: “Eurotunnel’s revenues have increased despite the migrant pressure which affects the Port of Calais and the Channel Tunnel.

“Eurotunnel appreciates the support of the British and French governments for this vital link for the European economy and the circulation of people.”