With mascots dressed as smiling fish and a police rock band, Thai authorities launched a "Happy Zone" at the weekend to improve the image of a city notorious for sex tourism.

Stung by foreign headlines portraying the seaside resort of Pattaya as "Sin City" and "The World's Sex Capital," Thailand's junta has begun a new effort to re-brand it.

But the contradictions in Pattaya highlight Thailand's challenge in tackling a side of its tourist industry that remains economically vital while being officially excoriated.