Public toilets in Beijing are deploying facial recognition technology to stop tissue paper thieves.

At the Temple of Heaven, a popular tourist site, toilet users have to stand in front of the smart paper machines with a high definition camera to have their faces recognised, according to Huanqiu, a publication affiliated to the People's Daily.

Each toilet user can only get a piece of paper measuring 60 cm (24 inches) to 70 cm (28 inches) each time. If they wish to get more paper, then they are required to wait for nine minutes.

Toilet users are required to remove their hats and sunglasses to have their faces recognised

Six machines have been installed in the toilets to stop tourists from taking paper to use at home.

Users are required to remove their hats and sunglasses to have their faces recognised.

Following a screenshot photo of their faces, an automatic roller is then activated to provide the user with tissue paper.

If the same person appears within a short time, the device will refuse to roll out paper.

Watching you: A toilet user reads the instructions for use of the smart paper machine

The machines are installed in three public toilets so far. The Temple of Heaven management said it is a pilot scheme to see if visitors are accepting of the new technology, The Beijing News reported.

The new toilet facility has attracted thousands of comments on Weibo, China's microblogging platform.

'Probably they should not provide tissue papers for free in the first place,' one user 'smiling crab' noted.

'This smart paper machine will be vandalised very soon,' another user 'coke N' said.

'From now on toilet users will be embarrassed to take tissue paper,' one user 'vintage lover' commented.