DESPERATE migrants are swarming the Port of Calais attacking trucks and overwhelming police as they truckers queue awaiting access to the Eurotunnel to Britain, reports the Freight Transport Association (FTA).

Violent scenes witnessed in and around Calais have been described as "unprecedented" by the (FTA), reports Lloyd's List. 

Touring the Eurotunnel facilities on what was expected to be the busiest day of the year for vehicles travelling through Calais, the FTA's manager for road freight and enforcement policy Chris Yarsley said he saw thousands of migrants attacking trucks as they queued on the motorway.

"I am flabbergasted at what I have seen today; there were literally thousands of migrants benefitting from the queue of slow moving traffic on the roads around Calais. They were attacking vehicles, breaking the locks of trucks, slashing roofs of the lorries and climbing in the back of them," said Mr Yarsley, who is based in Brussels.

"French police were highly visible and were taking extreme measures to break up the crowds including using tear gas and closing the motorway in order to control the situation, but appeared to be overwhelmed by the numbers," he said. 

"The migrants appeared to be organised in their attacks, as we were told of disturbances in the town centre which diverted police attention allowing opportunities for incursion attempts, and migrants took advantage of traffic being slowed on the road outside of the security fencing," Mr Yarsley said.

The FTA estimated that GBP89 billion (US$132.5 billion) worth of UK trade passes through Calais every year. Previously, FTA has written to the Mayor of Calais, and the UK's Foreign Secretary and Prime Minister calling for action on the worsening situation for its members in the French town.

Said Mr Yarsley: "The situation is totally unacceptable ?the area is clearly in crisis. Truck operators and their drivers are in the firing line ?sometimes literally. Whatever your views on the plight of migrants and asylum seekers, no one has a right to threaten, intimidate or physically attack drivers and other innocent bystanders.

"FTA expects and demands safe passage for truck drivers and others going about their lawful business. This must be the primary concern of French and British governments before someone gets seriously injured, or even killed."