PATTAYA, Thailand (Reuters) - 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.

“I want people to see that we are not like what they say. We are not allowing prostitution in these entertainment places,” provincial governor Pakkaratorn Teianchai told reporters on the infamous Walking Street in Pattaya, southeast of Bangkok.

Less than 10 meters (yards) away, women accosted foreign men to offer sex for 2,000 baht ($60). Others lined up with numbers so customers could take their pick. Masseuses in miniskirts offered “happy ending” massages whose euphemistic title has nothing to do with the Happy Zone of the authorities.

“Everyone is here to make a living,” said one 35-year-old woman who came originally from a village in central Thailand. Tagged with the number “136”, she declined to give her name.

“I would rather be a waitress, but then I couldn’t send my children to school and I want them to have a better future than this,” she said.

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In fact, sex tourism is not growing as fast as other aspects of Thailand’s tourist industry - the only bright spot for an economy whose expansion has been by far the slowest among major Southeast Asian economies since the 2014 coup.

No official figures show its scale.

But there is an indication in the balance of male to female visitors. In 2012, there were nearly 6 men for every 4 women. In 2015, the numbers were pretty much even, according to figures provided to Reuters by the tourism ministry.

Sex tourism began in Pattaya when it became an R&R spot for U.S. soldiers during the Vietnam War, though prostitution is just as evident in parts of Bangkok and other resorts.

The number of female sex workers in Thailand was put at over 120,000 in a 2014 UNAIDS report. Some estimates run to double that and not all the women who get paid for sex are full-time prostitutes.

Given a 305 baht ($8.80) a day minimum wage, the chance of earning several times more is an obvious lure, particularly in poorer rural regions.

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CRACKDOWN

The latest of many crackdowns in Pattaya happened after foreign newspaper reports last month, which drew an angry response from junta leader Prayuth Chan-ocha, for whom bringing order is a mantra.

A handful of bars were raided. Bar owners and working women were fined. Scared to venture out, tourists looking for sex stayed in hotels. Street vendors and shops saw sales tumble. The money which flows to all levels in the city - including law enforcement agencies - fell off.

The Happy Zone approach is a softer way to try to show that something is being done. If it works on Walking Street, the idea will be spread to the less sanitized side streets - the sois.

Businesses in the Happy Zone are asked to make the area feel safer, there are increased security patrols, police launched a mobile phone app for visitors to summon them in emergency.

“This is a pioneer project to organize a tourist destination and elevate it to promote Thailand’s quality tourism,” Apichai Krobpetch, chief of Pattaya city police, told Reuters. “We will also stamp out prostitution in the area.”

There was no sign of that at the weekend.

In fact, Pattaya’s sex industry has become an attraction in its own right for the millions of Chinese who make up about one in three visitors to Thailand.

Led by guides with pennants, the Chinese tour groups thread quickly along Walking Street, past the go-go bars and the beer bars where young Thai women sit down with foreign men.

They only pause to take pictures.

“We just came here to see. That’s all,” laughed twenty something saleswoman Linda Sieng in a group of 11 tourists from Guaghzhou in southern China.

($1 = 34.6 baht)