NINETEEN head shops that previously sold a range of legal highs which were recently banned remained open this weekend selling a range of ornaments and drugs paraphernalia including pipes and bongs.

There were previously more than 100 head shops around the country. All of the owners have complied with the new laws, which has made it a criminal offence to sell all psychotropic substances. All these substances have been removed from the stores.

Detectives expect the 19 head shops that are currently open will be forced to close down soon. "Some of these stores were making over €10,000 in one weekend and now they are reduced to selling pipes and bongs. There isn't much money in that – it is unsustainable," said a source.

Detectives from the Garda National Drugs Unit (GNDU) will continue to visit the stores in uniform as well as in covert operations over the coming months, posing as customers enquiring if it is still possible to buy the now illegal substances.

If a shop is caught selling these products, it faces prosecution and its owner a jail term of up to five years.

There were concerns that some of the substances previously sold at these stores, such as mephedrone, might begin to be imported and sold by drug dealers. But this has not proven to be the case.