Bands of migrants congregate at the side of the road near the port in Calais.

When a lorry slows half a dozen men run towards it and attempt to prise open the back doors, desperate to get in any way they can.

Kent hauliers say the situation in Calais is worse than it has ever been and some firms are avoiding the French port altogether until the situation improves, routing freight through nearby Dunkirk.

The problems are so bad now that the Freight Transport Association has warned drivers not to take rest breaks within 60 miles of Calais.

Murray Donaldson, Director of B and M Express Freight, said: “It’s got to the point where it’s not worth locking the back up because they’ll just cut a hole in the side. It’s the ongoing damage that’s the biggest problem.

“It’s worse than ever. We’ve got them running alongside the lorries trying to get in. If it’s busy and you have to queue you’re in trouble.

“You can’t park within 50 miles of Calais unless it’s secure, you can’t fill up near Calais - it’s a very difficult situation.”

Video: Illegal immigrants swarm around lorries in Calais

Mr Donaldson estimates some £2,000 worth of damage has been done to his fleet this year already.

And hauliers face heavy fines if they are caught with stowaways on board.

Firms face fines up to £2,000 per person and the Freight Transport Association is warning drivers to be extra vigilant.

Natalie Chapman, of the Freight Transport Association, said: “You can fit quite a few people in the back of a lorry so drivers and their employers can face some pretty hefty fines.

“We’ve been advising members to make their lorries as secure as they can be and if possible to fit alarms.”

It’s not just lorry drivers who have been told to be on their guard.

Motorists with caravans, motor homes and even family cars have also been targeted in recent days as migrants try to make the journey across the channel.

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