The case of a prostitution group, in which a policeman was involved, was heard in No 2 Intermediate People's Court recently, according to Beijing Times.

A couple named Wang Aiguo and Sun Meiyu and their son Wang Sijia, were charged with organizing prostitution, blackmail and offering bribes.

The policeman, 46, is alleged to have tipped the group off about local police prostitution operations since the first half of 2007.

In addition to free services in the five bath centers the group ran, the man, who used to be a police supervisor with the former Chongwen district branch of Beijing Municipal Bureau of Public Security, is alleged to have received a car worth 715,000 yuan from Wang last March.

"The couple just made use of me to protect their illegal business," the offender told Beijing Times after admitting taking bribes.

Local police rounded up the family owners of the five bath centers, together with more than 100 sex service providers last April, after an investigation was launched following a report from a customer who claimed to have been blackmailed for 13,000 yuan in a bath center owned by Wang.

The sex service providers remained silent after they were detained by local police last March and were released in 24 hours. Some claimed to be the girlfriends of customers or practitioners of body art.

The bath centers are alleged to have made more than 30 million yuan and about two thirds of the bath centers' revenues came from the sex service, according to the cashiers of the bath centers.

Aside from 54 major offenders, most of the sex service providers have been released without charge or trial after reeducation through labor or administrative detention.

Code words and jargon were used for staff to inform security guards a sex service was in progress.

The court will announce the verdict later.