More than 800 so called “lethal highs” have been permanently removed from the shelves after court action by KCC Trading Standards.

Branches of UK Skunkworks in Gravesend, Maidstone, Canterbury, Ashford and Sheerness have been prevented from selling the products, which mimic the effects of illegal drugs.

It follows a series of raids on 14 stores by officers from Kent and Medway Trading Standards and police in July, when thousands of legal highs were seized.

It is part of efforts to stamp out the substances and the dangers they pose - after the KM Group mounted a campaign to crack down on their sale.

At Dartford Magistrates Court on Monday it was held that the products were unsafe and that there were deficiencies in their labelling.

Similar decisions involving non-Skunkworks premises have been taken in the past few weeks by magistrates in Maidstone and Canterbury.

It total 50 samples were seized from Skunkworks UK in Maidstone, 19 from its Gravesend store, 50 in Canterbury, 38 in Ashford and 33 from Sheerness.

KCC Trading Standards Manager Richard Strawson said: “We are delighted with this decision. Skunkworks did not oppose our application and the forfeiture order was made. We are pleased that the court has agreed with our view that these products are not safe.”

The substances produce similar effects to illegal drugs, such as cocaine and ecstasy, but are not controlled under the Misuse of Drugs Act.

They cannot be sold for human consumption, but are often sold as bath salts or plant food to get round the law.

To comply with consumer law, traders must know precisely what is in each of the products they sell and what risks are associated with the ingredients.

Mr Strawson said: “We have been concerned for some time about the dangers posed by these products. Three people have died in Kent as a result of taking them, and across the nation they were linked to the deaths of 68 people in 2012.

“Trading Standards and the police have been working together to find an appropriate course of action that will get them off the streets.

“We are hoping that this action, taken against the country’s biggest trader in these dangerous goods, will result in similar action by other local authorities.”

Kent Police Superintendent Lee Russell, who helped co-ordinate the raids last summer, said: “We believe new psychoactive substances (NPS) pose serious health risks to anyone who uses them.

"Just because people have been able to buy something legally, does not always mean that it is necessarily safe for human consumption and what worries us greatly is that no one knows precisely what each individual packet contains.

“I’m delighted that the courts have recognised that the NPS which were being sold in Kent are unsafe products.

"Additionally, magistrates have stated that they are convinced that NPS are manufactured to be consumed, removing the guise that they are not for human consumption.

"Some premises have operated on the fringes of the law attempting to hide behind the excuse that they were not for human consumption, but the courts have now decided otherwise.

“More than 2,000 dangerous substances have now been permanently removed from circulation and will be destroyed and we will continue to work with our partners to prevent harm to the residents and young people of Kent and Medway.”

But UK Skunkworks spokesman Eugene Lusardi said the court's decision was "flawed", saying there was no persuasive evidence to prove the products were harmful.

He maintained that they were never sold for human consumption.

He told the Kent Messenger: "On a broader level, it is clear that prohibition doesn’t work.

"The forfeiture of goods from our shops clearly won’t do anything at all to the market for those goods - nor to our business, most of which is unconnected to these particular products - it will just force it underground, compromising quality and ensuring that the relevant quality control and safety information pertaining to the products does not reach those buying them."