WARNING: Graphic

AN AUSTRALIAN man has been busted for allegedly hosting “wild sex orgy” parties with sex workers on boat cruises in Thailand.

Stephen Allan Carpenter, 49, allegedly boasted to customers that drunk 19-year-olds would “take six blokes at once’’ on-board the booze-fuelled luxury private charter boats in Pattaya.

Explicit pictures of the X-rated adult parties show naked women surrounding middle-aged men and others performing lesbian sex shows with toys.

Thai police allege they caught Carpenter in an undercover sting after they heard about the orgies through the ads he posted online on Facebook and Craigslist.

In the covert operation, police allege they negotiated a trip with Carpenter when he told them

“anything goes’’ and bragged that the “stunning girls’’ plucked from local clubs and gogo bars were “really dirty’’ after being “filled up with grog”.

Police will allege on December 6 last year Carpenter posted an advertisement on his Facebook account promoting his business, AUSTHAI Tours, where he described his service arranging a chartered boat trips with sex workers on board.

Another advert on Craigslist for a ‘”wild boat orgy’’ allegedly showed six naked Thai women surrounding a western man.

Police allege they contacted Carpenter earlier this month and he replied with explicit pictures and videos from on-board earlier private parties.

They were allegedly sent pictures of different women who took part in the orgies.

Police allege Carpenter told them customers paid 55,000 baht ($2277) to charter the “high class cruiser yacht’’ for a six-hour party filled with at least eight girls, food and drink.

Customers would then allegedly pay the girls extra for their sexual services but police said Carpenter said the sex workers were “desperate’’ for customers because it was low-season in the tourist industry.

Police allege Carpenter agreed to a price and asked the undercover operative to pay half as a deposit.

They then used the transaction record as evidence to get an arrest warrant from a Pattaya court.

Thai police officer Dulayaphat Techaphonchayasin, who is leading the investigation, said Carpenter was charged with mutual consent to satisfy the lust of others, engaging women in obscene acts with men or women, and taking away people to commit acts of prostitution, even if the person was consenting.

“The suspect escaped after the arrest warrant but was tracked down to Muaklek, Saraburi,” he said.

“The accused advertised his events on Facebook and other websites.

“In messages to undercover police the suspect agreed details of the parties and sent his bank details for the transfer of money.’’

On arrival in Pattaya for further questioning, Carpenter faced additional charges of violating the law regulating types of work foreigners are permitted to do in Thailand, and overstaying his visa.

He is also accused of violating the computer crime act by posting nude images online.