The ephodrine and caffeine-based pill sells for just 100 baht (US$2.56). Hundreds of millions of ya baa pills are being produced in neighboring Burma, mainly by the United Wa State Army, a 20,000 strong insurgency group recognised as one of the world's biggest armed drug trafficking units.

The UWSA, notorious for its heroin production in the Golden Triangle, has converted many of its heroin laboratories into ya baa clinics over the past three years because of the massive profits involved in producing the pills. The UWSA make the pills for less than 5 baht (13 US cents) and smuggle them into Thailand along an 800-km stretch of largely unguarded border.

For the past five years, Thailand has effectivelybeen the sole market for the UWSA's ya baa pills. But the UWSA is looking to expand its markets to other countries in Europe and the Asia-Pacific, according to Sorasit Sangprasert, deputy secretary general of Thailand's Office of Narcotics Control Board.

``We can see some of the drugs are already being smuggled out of the country -- some are going to Switzerland, some to Japan, Korea and Indonesia,'' Sorasit stated.

The United Nations Drug Control Program estimates that 45 per cent of the world's heroin comes from Burma, with the UWSA recognised as the major source.

The biggest seizure of ya baa pills being smuggled out of Thailand came last year when authorities found 36,000 pills at Bangkok's international airport destined for Japan, according to Sorasit. Ya baa has gained infamy in Thailand for its devastating side-effects. Although it causes similar feelings of power and limitless energy as those associated with other types of amphetamines such as Speed and Ecstasy, it can cause massive bouts ofparanoia.

Local media in Bangkok regularly show violent incidents where ya baa addicts have stabbed themselves to death. Television news bulletins show police shooting deranged men who, believing they were being threatened, have fired guns or wielded machetes at innocent strangers.

Ya baa has overtaken heroin over the past five years as the biggest drug problem for Thailand's 60 million people. The latest government figures show 300,000 heroin addicts in Thailand, compared with estimates of more than one million ya baa addicts and countless more occasional users.

The number of ya baa addicts has risen five-fold since 1993. For its part, the Burmese government has given the UWSA approval to develop Mong Yawn town into a city over the next five years.

-- The Observer News Service