Two shopping centres in the southern Chinese city of Shenzhen have installed new glass toilet cubicle doors, which are designed to turn from opaque to transparent when someone is smoking inside.

A notice on the doors reads: “The glass will turn transparent if you smoke. Hold your urge to smoke if you do not want to become famous online.”

Their introduction follows local officials’ failed attempts to tackle indoor smoking through publicity campaigns and fines, the South China Morning Post reports.

However, local lawyer Lu Weiguo of Guangdong Gehou Law Firm warned that the shopping centre could face legal liability if the doors malfunction and turn transparent without the presence of smoke.

Nonetheless, shoppers and social media users are said to be supportive of the new technology.

“Finally, there is an effective measure to tackle smokers,” one social media user said.