SURAT THANI: The latest Full Moon party at Koh Phangan late last month did not only draw Thai and foreign revellers. The famous moon festival also drew authorities, who went there for a not-so-merry objective -- to crack down on drugs.

Narcotics use had been reported at Koh Phangan for many years, yet officials did not focus their efforts on the island, partly because the drugs were mainly used by tourists during parties.

However, the Office of the Narcotics Control Board (ONCB) decided to turn its attention to the spot, where news of drug use is threatening to tarnish the image of the resort island, just off the Surat Thani coastline.

Koh Phangan is not the only target of the ONCB's latest drug crackdown. They are also cracking down on drugs at other tourist destinations in the province -- namely Koh Samui and Koh Tao.

"They all must be placed under a microscopic watch. The province's drug problem has been hard to deal with," said Sirinya Sitdhichai, the outgoing secretary-general of the Office of the Narcotics Control Board, as he led hundreds of officers to Phangan early last week.

The inspection of Koh Phangan was a final trip for Mr Sirinya, who retired Sunday. Niyom Toemsisuk, the new chief of the ONCB, accompanied him.

The widespread use of narcotics in these world-renowned islands is just a tip of the iceberg of the southern region's drug problem.

In fact, the two are linked, which shows the drugs problem on the islands is not confined to tourists at all.

In addition to news of drug parties among foreign tourists, the police have learnt that the province has been used as a transit point for drug smuggling to neighbouring countries, Malaysia in particular.

Around 70-80% of the drugs smuggled in the South are transported overseas.

The remainder is circulated in the province, mostly to revellers in Surat Thani's premier beach destinations.

As a result, Mr Sirinya decided to focus on three main islands in particular.

Surat Thani-based Don Sak police chief Sutthi Nitiakkharanon welcomed the ONCB's move to intensify drug searches at two major ports -- Racha and Sea Tran -- where ferries take travellers to Koh Samui.

The route is popular among tourists who will catch another boat at the island to Koh Phangan.

More officers will be deployed to conduct searches on the day the Full Moon party is held.

Smugglers often bring marijuana and crystal methamphetamine, often referred to as ice, which are highly popular among tourists on the islands.

Ice is usually priced at 1,000 baht per gramme in Surat Thani, but the same amount of drug is priced between 2,000-3,000 baht on Koh Phangan.

Smugglers deploy various tactics to escape drug searches, with veteran users and smugglers known to hide drugs in snacks, even in red curry paste packets.

This method prevents sniffer dogs from finding the drugs, Pol Col Sutthi said, so officials must rely on their experience to observe any irregularities instead.

"Just scanning travellers and their belongings before they go to the islands is no longer enough. We decided to do a double check on trips to and from the Full Moon party to mainland Surat Thani," Pol Col Sutthi said.

Recently, police decided to call for urine tests from travellers at piers for those suspected of being high from drugs, which has helped them arrest wrongdoers.

So far in this year alone, police have found 1,000 suspects guilty of drug offences, and sent many of them to prison.