Thailand's taxman setting his eyes on gamblers and prostitutes.

The suspicious Ukrainian-registered cruise ship was sailing peacefully in the bay of Pattaya when 100 heavily armed Thai commando troopers stormed the ship, sliding down ropes from Thai army helicopters hovering above the cruise liner, other Thai elite troops climbed onto the ship from high-powered police boats.

Once in control of the vessel, however, the commandos did not capture al-Qaeda terrorists, Tamil Tiger weapon smugglers or even local Thai drug lords. The ship's passengers were simply 100 Thais, indulging in Thailand's illegal passion for gambling.

In Thailand, most forms of gambling, except betting on horse races and Thailand's National lottery, are illegal. But that does not stop most Thais from courting Lady Luck wherever and whenever they can, including in hidden gambling dens, air-conditioned buses fitted dark windows and card tables or cruise ships, such as the Ukrainian cruise ship raided by Thailand's commandos.

People in Thailand gamble an estimated 612bn baht (US$ 16bn) a year, both illegally in Thailand and in about 33 legal casinos just beyond Thailand's borders, in Cambodia, a recent study showed.

Illegal gambling in Thailand is one of the biggest parts of the Thai flourishing underground economy: a non existing shadow world of gambling dens, illegal casinos, brothels, smuggling and trafficking networks that has operated for decades in Thailand under the patronage and protection of influential Thai politicians, police officers and bureaucrats.

Prime Minister Thaksin Shinawatra and the top leaders of the ruling Thai Rak Thai party (Thais love Thais) are eyeing the vast sums of tax-free money being generated by those underground economies in Thailand. Keen to cash in on these lucrative underground businesses to find more tax revenues to fund their expensive social programs in Thailand, Thaksin Shinawatra's government is trying to push the idea that those current underground activities should become legalized, regulated and taxed in Thailand.

Khun Pasuk Pongpaichit, a Chulalongkorn University economist who made a study of the underground economy in Thailand, said that by making those illegal businesses legal and regulated, it would become easier to control and tax them.

For Premier Thaksin the potential benefits of seeing those illegal underground activities regulated, would not only mean supplementary tax money in Thailand's coffers, but would also offer a opportunity to distribute more patronage under supporting politicians while choking the flow of black money to corrupt police officers and potential political rivals.

Prime Minister Thaksin has already proposed a national referendum on whether the government should license the so-called Las Vegas style entertainment complexes in Thailand, which would marry casinos with live shows and deluxe restaurants. But the people of Thailand remain deeply divided on his proposal to legalize gambling casinos in Thailand, many Thais fear that this could lead to more gambling, an activity that contravenes with the fundamental concepts of Buddhism in Thailand. While no time frame has been set, some well informed Thai officials predict that the first legal casinos could open as early as the beginning of 2004.

It's a huge opportunity for Thailand to make money, said one Thai analyst, and above all it opens up the area for legitimate business.

The government of Thailand is also moving, cautiously, to test the Thai public feeling about legalizing prostitution in Thailand, an industry estimated to involve about 200,000 women. Although commercial sex has long been tolerated in Thailand, prostitution was banned in the year 1928 and the women and venues involved nowadays remain vulnerable to abuse and extortion from the Thai police.

While many Thai politicians ignore the existence of this industry, prostitution and the sex business was forced on to the national agenda this year by Chuwit Kamolvisit, Thailand's "Massage Parlor King". His revelations, that he monthly had to pay millions of Thai baht to the local police, to turn a blind eye to the illicit commercial sex in massage parlors, has triggered the interest of the Thai government and Thailand's Tax Collector.

At a recent governmental seminar, prostitutes, brothel owners and their advocates argued that decriminalizing prostitution in Thailand would reduce women's vulnerability to extortion and stigma. Women in the Thai prostitution business are triply exploited, first by the venue owners, then by the Thai police and lastly by the clients and owners. Those women are not protected by the Thai labor law and thus cannot bargain for legal help.

For now, Prime Minister Thaksin, with his shrewd political business instincts, is not expected to push too hard on legalizing prostitution in Thailand, given strong opposition coming from the Thai middle class. Yet breaking the taboos surrounding gambling in Thailand could be a shrewd move to prepare the grounds for legalizing prostitution and the sex business, a prospect that many Thais find deeply worrying.

It is completely wrong move, said Khun Virada Somsawasdi, a professor of law and women's studies at the Chiangmai University. The current Thai government is more looking at the eventual tax benefit, rather than at the social protection for the Thai women involved in this business. It is pure economic greed at the expense of "Social Conscience" of the Thai people.