Police raided a spa allegedly employing underage prostitutes while bribing officials in northern Thailand.

Cyber Crime Investigation Bureau (CCIB) officers, acting on a tip-off from the influential anti-human trafficking group Immanuel Foundation, raided the Vida Spa in Chiang Mai province on April 23.

The establishment was reportedly a bawdy house disguised as a massage parlour, where male customers can have sex with girls aged around 16 to 18.

Police Lieutenant Colonel Khemathit Thongkham of the CCIB said: 'We raided the spa after receiving information from the Immanuel Foundation that the shop, masquerading as a health massage parlour, was prostituting girls under 18 years old. 

'We have been investigating the spa for over three years, but it was difficult to take action because they frequently switched locations to avoid arrest. This time, we finally had enough evidence to launch a raid and rescue the underage girls.'

Cops found that Vida Spa advertised its services through seedy online forums and a Twitter account, posting erotic pictures of the young girls with their faces covered.

The shop was reported to charge 500 THB (11 GBP) for a regular massage, 799 THB (17 GBP) for a massage with a 'happy ending', 1,300-1,500 THB (32 GBP) for a Nuru or body-to-body massage, and 3,000 THB (65 GBP) for sexual intercourse.

Police arrested the manager Natnaree Puangmala, 21, and also discovered a bank account registered to Patthanang Supacharn, 51, where the payments were deposited.

They also seized ledgers, receipts, computers, security cameras, and another bank account that allegedly made 20,000 THB (432 GBP) payouts monthly to officials of several organisations. Police have not clarified which organisations were involved.

Six underage girls were rescued. Officials said they will be interviewed by social workers before being handed over to the Office of Social Development and Human Security.

Meanwhile, Natnaree is facing charges of prostitution and operating a healthcare facility without a license.