Beijing, Aug 1 (IANS): Authorities in the Chinese capital have been urged to stem the entry of foreign sex workers following the arrest of four such women in a downtown club.

Police raided Qixingdao bar in Chaoyang district July 18 and arrested 15 suspected prostitutes, including the four foreigners, China Daily reported Wednesday.

Located in an office building close to many embassies, the bar was closed Tuesday, the Public Security Management Corps said.

Corps spokesman Ou Yang said the arrests were part of a citywide campaign against entertainment venues that allow obscene shows or prostitution.

Ou did not disclose further information about the arrested women, including their nationalities.

Many of the willing prostitutes are in China on student, tourist or temporary-worker visas, the daily said.

Another official was quoted as saying that foreigners worked as prostitutes not only in big cities like Beijing and Guangzhou but also in smaller areas.

"The majority of foreign sex workers are from neighboring countries such as Russia and Vietnam," the official said.

Prostitution is illegal in China. People face an administrative detention of 15 days if found working as prostitutes.