An American man has been arrested in a sting operation for allegedly running an online brothel service matching men in northern Thailand with Myanmar sex workers across the border, police said on Tuesday.

Kenneth Viggo Albertsen, a 66-year-old living in Chiang Rai on a retirement visa, is accused of running a website and Facebook page called "Burmese Border Chicks for Hire" that sold sex with Myanmar women for 6,500 baht.

The business brought women to meet clients on the Thai side of the border in Mae Sai and also offered to "guide" men into Myanmar for sex services, police said.

"He has been operating for at least 10 years," Colonel Jirabhob Bhuridej, deputy commander of Thailand's Crime Suppression Police, told AFP.

Police said Albertsen was arrested after arranging for two Myanmar women, aged 25 and 18, to cross into Thailand and meet undercover officers posing as clients at a hotel in Mae Sai.

He and the two sex workers, plus another Myanmar woman who allegedly helped arrange the meet-up, have been charged with procuring prostitution, which carries up to 10 years in prison.

The bust comes as Thailand is trying to shake off its reputation as a haven for sex tourists.

Yet while prostitution is technically outlawed in the kingdom, it is largely allowed to operate in plain sight, with huge glitzy "massage parlours" in Bangkok and brothels in towns across the rest of the country.

Bribes and widespread corruption help to insulate the lucrative industry from authorities.

The explosion of social media has also moved much of the business online, helping agents procure women and arrange sex services in the shadows.