Wearing dark glasses, a hood and a mask, the 15-year-old Filipino girl explained to the Philippine senate committee that she had been recruited as a masseuse.

It was not until later she found she would be prostituted out as one of nine females under the control of a Chinese boss who sold her body nearly exclusively to Chinese clients in Philippine hotels. Her boss would keep half her earnings, which began at 6,000 pesos per client and increased if she stayed overnight. And “Carina”, as she was referred to in the hearing, was not the youngest to be exploited. One of her coworkers was just 14.

The teenager’s testimony, given via a video link, was just one of the shocking insights the committee gained into the rise of Chinese prostitution dens in the Philippines at a special hearing on Tuesday.

The committee also heard from law enforcement officials, who directly linked the proliferation of the dens to the rise of Philippine offshore gaming operators, or Pogos, online gambling firms that are based locally but employ mainly Chinese workers and cater to customers in China, where betting is illegal.

“We only experienced these activities when Pogos were created, Chinese Pogo employees are the ultimate clients of these prostitution dens, and they entertain only Chinese nationals,” the National Bureau of Investigation’s Deputy Director Vicente de Guzman III told the hearing.

Lawyer Reynaldo Bicol, the field office director of the International Justice Mission Philippines, added that efforts to clamp down on the dens had been complicated by the use of private Chinese internet chat forums to facilitate the trade.

Senator Risa Hontiveros, chair of the senate’s committee on women, children and family relations, said her investigators had infiltrated groups on WeChat and Telegram, showing the hearing screenshots of various transactions.

One slide showed an advert for three nationalities of prostitute: Chinese were priced at 13,000 pesos for 60 minutes and up to 30,000 pesos for all night; Russians went from 12,000 pesos for 40 minutes (referred to as “fast food”) and up to 45,000 pesos for all night; Koreans were priced at 13,000 for an hour to 32,000 pesos for all night.

Another slide showed a specific set of sexual services on offer from the “Puding Club”, which it boasted were on offer 24 hours a day. Many of the slides contained pictures of women in skimpy clothing or partially naked.

Hontiveros described it as “a menu of services like a restaurant, and you just order the [prostitutes] from the app; it’s like Grabfood, you order, then [your order] will just arrive in your hotel or condo”.

Another advert she displayed said: “Brothers, we have new tea available, we welcome old customers to come and drink tea.”

Hontiveros explained that in the Chinese sex trade prostitutes were often referred to as “tea” to evade government online monitors.

Another slide showed pictures of a woman with the caption: “New car, highly experienced, superb, knows many styles and positions.”

In the past six or seven months, Philippine law enforcement agencies – which have openly admitted to being caught off guard by the sudden rise of the dens – have been raiding brothels across the country and rounding up the prostitutes. However, many of the prostitutes have valid tourist visas, leaving police a dilemma over what to do with them.

De Guzman, of the NBI, said that “when we conducted our first operation against traffickers of Chinese women, I don’t know if the Chinese embassy was very busy at that time, we were suggesting that we turn over the rescued victims to the Chinese embassy but unfortunately we got no reply.”

After a week, he said, a group of Chinese officers met counterparts at the NBI to ask for “collaborative efforts in combating transnational crimes”.

Senator Hontiveros pressed for the suspension of the “Visa Upon Arrival” scheme, which makes it relatively easy for Chinese citizens to enter the Philippines.

The senator said the scheme had “readily assisted the rise of Chinese criminals in the country”.

“We need to look into suspending Pogo operations because they attract criminals into our country,” she added. “We cannot be a nest of Chinese prostitution.”

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