The Criminal Court handed down jail sentences Monday to six people involved in the prostitution of underage girls in the Victoria's Secret Massage case, but dismissed human trafficking charges against them.

The court sentenced Satthatham Chaengchai, the manager of Victoria's Secret Massage, and Boonsap Amornrattanasiri, 55, to three years and four months in jail each for prostitution of girls aged no older than 15 in violation of the Criminal Code and the Prostitution Act.

The court also sentenced Sasithorn Weerathepsuporn to eight months in jail on a charge of the prostitution of girls aged below 15.

She was the authorised partner of Amarin Onsen Partnership, which operated Victoria's Secret Massage.

The court dismissed the case against Amarin Onsen Partnership and handed a six-year jail term to Decha Sakorndecha for violating the Criminal Code and the Prostitution Act.

Decha was accused of driving underage girls from Bangkok to Songkla's Sa Dao district for prostitution in Malaysia.

The court also sentenced Satthatham, Boonsap, Chainarong Unsuk and Eknapat Jaruwatpathomkul to 16 years in jail each, and Sasithorn to seven years and six months for committing offences against women aged 15 and above but not over 18 years old.

This means Satthamtham and Boonsap received combined jail sentences of 19 years and four months each, and Sasithorn was handed eight years and two months.

The court dismissed human trafficking-related charges against all the suspects.

It also threw out the case against Amarin Onsen and Davis Silverstar Co, reasoning that the companies were only legal entities involved in renting locations.

The court also acquitted Boonchaliew Chanphim. The court said he rode a motorcycle to take the underage girls to the massage parlour without any knowledge of how old they were, and that he was not involved in procuring prostitutes.

After the ruling, a source at the Department of Trafficking in Persons under the Office of the Attorney-General said the department will appeal against the dismissal of the human trafficking charges.

The high-end "soapy massage" parlour in the Rama 9 area of Huai Khwang district of the capital was raided in January.

More than 80 women, mostly from neighbouring countries, discovered there were believed to have been forced into prostitution. Among them were 14 girls aged under 18.

Authorities widened the investigation and later discovered that 20 state officials, including senior police officers, may be implicated after incriminating documents were found on the premises.

Earlier, the Department of Special Investigation (DSI) teamed up with the Anti-Money Laundering Office to freeze assets valued at 100 million baht which belonged to Victoria's Secret Massage owners and others suspected of having roles in human trafficking.

The Jan 12 raid on the parlour also found documents allegedly indicating police and some influential state officials were given complimentary sexual services.

Former politician Chuvit Kamolvisit told the DSI he suspected Victoria's Secret Massage was part of a criminal syndicate which targeted girls aged between 12 and 18.