The full weight of the law should come down on persistent legal highs sellers - with jail considered as an option.

That's the plea from Julian Brazier, MP for Canterbury and Whitstable, who was speaking after a series of raids across Kent on stores suspected of selling the drugs.

Mr Brazier said he was very pleased that the raids had taken place yesterday, and hoped it might lead to some - or all - of the stores closing.

But he called for more powers for councils or police to get injunctions against the shops selling the over-the-counter drugs.

If sellers persisted in peddling the substances, often referred to as herbal incense or similar, there should be an option to jail them, he said.

It was also important to get the message across to youngsters of the dangers of the drugs - as teenagers may think legal means safe.

He said: "I think it's important to that they are told how dangerous these drugs are.

"But I am also in favour of changing the law to make it easier for the police to do their jobs."

He attacked the message on many packets "not for human consumption", which gave shops a loophole - despite packets being called obvious names such as Go Caine and Synthacaine.

Tracey Crouch, MP for Chatham and Aylesford, echoed Mr Brazier's calls.

Both had joined forces to lobby Parliament for a change in the law on legal highs.

She said the raids were a "fantastic outcome of the campaign the KM Group has been running to raise awareness of the safety of legal highs".

But the MP warned of complacency when dealing with the drugs.

She said: "Although they are deemed legal they are incredibly dangerous and I think that it is right that the enforcement agencies are doing their best to rid legal highs from our streets."

She didn't think enough was being done to make youngsters aware of the potentially life-threatening dangers of the drugs.

She said: "Because they use the word 'legal' in them people assume they are safe to take.

"What's quite clear from recent cases, which have threatened the life or unfortunately taken the life of youngsters, is that they are incredibly dangerous."

But a user quizzed during the raids said he didn't think there was harm in them.

Charlie Cooper, in Canterbury, said he bought stuff marked up as herbal incense and smoked it.

He said some people used it for that purpose, but he preferred to smoke the high - he wouldn't touch pills or powders.

Although it was marked "not for human consumption" he said he knew what he was doing, and knew how to handle the substance.