Shoppers queue at the registers at a Coles supermarket in Sydney on Thursday, Oct. 22, 2015. (AAP Image/Paul Miller)

A dozen Coles supermarkets in Melbourne have reportedly installed tablet computer-sized cameras on top of its self-service checkouts to combat shoplifting.

The cameras have been deployed directly above the self-service monitor, as Maroondah Leader first reported, and shoppers can see themselves scanning items on the camera screen.

A spokesperson for the supermarket told Yahoo Finance that the new security technology is going through a trial in selected stores to reduce self-checkout theft.

“While the large majority of our customers do the right thing, it’s not fair that a small number of people get away with doing the wrong thing,” the spokesperson said.

View photos Coles self-serve checkout security camera. (Image: Imgur) More

The presence of the cameras was well signposted and meets legal requirements, according to the spokesperson, with the Coles’ privacy policy available to view online.

One Reddit user suspected the cameras were more about making people self-conscious rather than directly catching theft.

“There is a thought that people see themselves on screen it can reduce theft,” said the commenter.

“Coles are more about prevention than apprehension. Having cameras at checkouts is the same as having cameras down the aisles and in the entrances of buildings.”

Eight million transactions go through self-serve checkouts each week at Coles.

Undercover security officers are also deployed in supermarkets nationally, the Coles spokesperson said, to catch thieves red-handed and hand them over to police.

The Melbourne trial comes after a Coles in northern Sydney installed similar security cameras and screens on top of baby formula shelves, in order to enforce the per-customer limit on such products.

Baby formula in some Australian supermarkets have sold out in seconds as entrepreneurial types snap them up and on-sell them to Chinese customers at a profit.

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