The use of facial recognition to reduce the theft of toilet paper in restrooms in Beijing's Temple of Heaven Park were accused of being unnecessary and overly intrusive.

The park installed six USD 720 facial-recognition toilet paper dispensers in its public restrooms to address the issue of visitors taking excessive amounts of free toilet paper.

The system scans a person's face before dispensing a 60-70cm strip of toilet paper, and will not dispense more paper to the same person until after nine minutes have passed. 

The move divided users, with some saying it was inappropriate and intrusive, whilst others reckoned it was necessary and long overdue. 

Park authorities told Beijing Wanbao that the daily amount of toilet paper used in its toilets had reduced by 20 percent. But some reports also said the machines could be unreliable, and caused delays and confusion.

As CNN noted, visitors say the biggest targets of the new crackdown are older people who stuff their bags and pockets full of toilet paper to take back home. 

Many public restrooms in China do not provide toilet paper, with visitors expected to bring their own.