The traditional Chinese performing art of Bianlian, classified as a state secret, has been leaked overseas by artisans desperate to make money, state media said on Monday.

In a Bianlian, or mask-shifting, actors swiftly shift from one mask to another showing different faces in the twinkling of an eye in an exhibition that has fascinated audiences for centuries.

The art, which has its origins in the southwestern province of Sichuan, is traditionally performed on the stage of Chuanju operas and its technique, which involves sleight of hand, has been closely guarded as a trade secret for generations.

But now Bianlian, classed as a secondary state secret by the Ministry of Culture since 1987, has been sold abroad by artisans keen to cash in on the art, Beijing Morning Post reported.

The report quoted veteran mask-shifting master Wang Daozheng as lamenting that a corrupted version of the art is now performed in Japan, South Korea and Germany.

"Mask-shifting is a highly-skilled art which has been passed down from many generations of Sichuan artisans, but now it has become a means for money and fame for many actors ... I feel heartbroken," Wang was quoted as saying.

The report did not say whether authorities plan to take any action aimed at preventing further leaks of the secret.

AFP