Four police officers and two other people were brought before court in Xi'an on Dec 17 on suspicion of using entrapment to earn commissions.

The police defendants include the Hujiamiao police substation head surnamed Li, a political instructor surnamed Liu and two other officers from the station surnamed Bai and Liu. They were charged with corruption and abusing their power, according to Xi'an-based Huashang Daily.

They are suspected of having used entrapment to impose fines since 2009, according to a public prosecutor at court.

The case was exposed after a local TV station revealed that the Hujiamiao police substation was suspected of having used entrapment to fight prostitution in August.

According to a victim surnamed Zhang, he was quickly detained by two plainclothes police officers after he entered into a foot massage center on Huaqing road.

He was fined 3,000 yuan for visiting a prostitute and was not given any receipt for paying the fine.

Zhang said the foot massage center, which had been immediately closed when he was detained, was reopen for business again about 20 minutes after he was fined.

The "prostitute" was also seen to return to the center to resume her work.

After the local TV station broadcast Zhang's story, Du Hangwei, director of the Xi'an Bureau of Public Security, immediately ordered the establishment of a special task force and launched a thorough investigation.

The court has not yet ruled on the charges.