A 64-year-old man was shaking with nerves as he tried to smuggle almost £300,000 worth of a drug commonly known as monkey dust through the Channel Tunnel.

Mechanical fitter Peter Harness told Border Force officers at Coquelles he was returning from a business trip in Holland when his VW Polo was stopped in November last year.

But Canterbury Crown Court heard he was "visibly shaking" and could not hold his phone still as he tried to provide proof of his overnight stay.

His anxiety then increased when officers searched his rucksack and beneath his clothes found 14 silver-taped packages.

Each contained 1kg of methylenedioxy-a-pyrrolidinohexiophenone (MDPHP), a class B drug said to have an effect similar to cocaine and amphetamine, and with an estimated street value of £280,000.

Prosecutor Bridget Todd told the court Harness was the only occupant in the hire car when it was pulled over.

"He explained he had travelled from Holland from a business meeting. But he had no record of his trip, no hotel booking or receipt," she said.

"As he showed the officer an address he was visibly shaking and could not hold his phone still.

"The vehicle was a hire car, and when he tried to show a document he was again visibly shaking."

The officer then opened the boot and a door to the vehicle and spotted the holdall.

"At that point the defendant intervened and said those were all his clothes and started to take them out. Again, he was anxious," continued Miss Todd.

"He was told it would still have to be searched and underneath a layer of clothing were the 14 packages."

Harness, of Immingham in Lincolnshire, gave a 'no-comment' interview but later admitted drug smuggling.

Melanie Krudy, defending, said he had "foolishly" agreed while on one of his regular work trips abroad to take the bag in return for being paid up to £5,000.

She said there was no evidence to support any suggestion that the dad, whose youngest child is just a few months old, was in any way more involved in the drugs operation.

She added he had been put up in the hotel by the firm he was working for at the time and drove back to the UK in a hire car because his own vehicle had broken down.

"Of course he was shaking because he knew the search was going to find the drugs," explained Ms Krudy.

"He had got himself in debt, was given the opportunity to earn a bit of money on the side, and was stupid enough to take it.

"Those more sophisticated rely on the stupidity and desperation of men like Mr Harness."

Jailing him on Tuesday for three years, Recorder Daniel Stevenson said: "It's impossible to overstate the harm the importation of wholesale drugs does to society.

"You were a courier but your role was clearly significant. You were highly trusted and expecting to be paid up to £5,000."