Joint authorities in Taoyuan district, northwest Taiwan, have closed down a 10-member prostitution syndicate and placed them under arrest for various offences against public morality including trafficking women and forcing them into prostitution by drugging them.

A Taiwanese man surnamed Lee, who was identified as the ringleader of the syndicate, linked up with a Thai man who recruited women from Southeast Asian countries. The Thai sent the women to Taiwan by advising them on how to use the 14-day visa-free travel entry system, the China Times reported.

Each woman would be sent to a designated ensuite room, where they had to conduct illegal sexual services, priced between NT$2,000 and NT$2,500 (US$65-US$80) per 40-minute session.

Investigations determined that Lee would take at least NT$1,200 (US$39) per transaction.

Lee and his associates also advertised sexual services online, and switched their digital information control center every two or three days to evade the authorities.

Immigration officers, together with officers from Zhongli Precinct of Taoyuan Police Department raided premises in the city, where a total of five foreign women were arrested.

The women, including two Thai, one Vietnamese, one Indonesian, and one mainland Chinese, all tested positive for illicit substances, which were allegedly given to them by the syndicate who used drugs to keep the women awake and under their control.

The female victims are now being detained by the immigration authorities, pending repatriation. Charges will reportedly be pressed against Lee and his associates after further investigations are carried out.