BANGKOK (AFP) - A craze in Thailand for pampering lifelike dolls to bring good fortune doesn't seem to have done the trick for some vendors, who on Tuesday (Jan 26) were raided by police on charges of tax avoidance.

Known in Thai as "luk thep" (child angels), the pricey dolls, which can cost up to US$600 (S$857), were first popularised by celebrities who claimed dressing up and feeding the dolls had brought them professional success.

Doll-mania has since taken off across deeply superstitious Thailand, with adults bringing the figures to Buddhist ceremonies, restaurants and even on planes, where they have reportedly been issued seats and served mid-flight refreshments.

But after Thailand's police chief warned this week the fad was going too far, officers on Tuesday confiscated more than 100 dolls and arrested three vendors in Bangkok for allegedly failing to pay import taxes.

"Mostly they imported (the dolls) from China," Colonel Kriangsak Kanrayawattanajaroen, deputy commander of the Economic Crime Suppression Bureau, told AFP.

He added that the vendors had avoided paying more than 100,000 baht (S$3,984).

The bust followed reports this week that Thai Smile Airways was offering ticketed seats and meals to the dolls, accommodating owners who did not want to stow them as carry-on luggage.

Thai media published a leaked airline memo that defined the "child angels" as "a doll that is alive".

The memo said the dolls should be placed in window seats so as not to disturb other passengers and that seatbelts should be worn during take off and landing, according to reports.

Thai Smile declined to comment when contacted by AFP.

Thai anthropologist Visisya Pinthongvijayakul told AFP that while the angel doll trend started only last year, the practice has roots in the ancient occult worship of preserved foetuses thought to contain a child's spirit.

More than 90 per cent of Thais identify as Buddhist. But the country's Buddhism is known for its syncretism, comfortably blending many animist and Hindu traditions into daily worship.

Mr Visisya said he has seen many shopkeepers and vendors buy the new angel dolls in hopes the talismans will boost sales during currently bleak times for Thailand's stuttering economy and ongoing political instability.

"From the perspective of Thais this is a very uncertain time," said Mr Visisya, citing the plunging price of rubber and the ruling military junta's lid on dissent.

"I think this is a practice that reflects an unstable and critical moment in Thai society."