Coles shoppers startled by little-known security measure as supermarket fills with smoke

It comes as the supermarkets attempt to stamp out the rise of theft in stores.

The "aggressive" rollout of anti-theft technology in supermarkets of late has attracted the ire of frustrated shoppers, many of whom admit they often feel like "criminals" when shopping.

Smart gates, overhead cameras and Coles' new checkout security gates have been rolled out in an attempt to stamp out theft, and are visible across stores nationally — but there's another, lesser-known security measure that's baffling shoppers.

A Coles shopper first noticed it while shopping at the Clayton store in Melbourne on Friday night and was shocked to see the supermarket "fill with smoke". The shopper claims he heard "a loud pop" on his way to the checkout before a plume of smoke gradually filled the air, almost covering the checkouts completely.

Coles store filled with fog.
A Coles store in Melbourne filled with fog with shoppers inside. Source: Reddit

Photos posted online show the inside of the store barely visible through the smokey haze. "There was no burning smell and everyone in the store was relatively calm, however, the fire alarm did go off," he explained in a post on Reddit. "The smoke eventually went away after 2-3 minutes," he added before asking, "does anyone know what it may have been?".

Reason for smoke explained

Yahoo News Australia understands that a fog machine was responsible for the in-store mayhem on Friday. While not part of the supermarket's recent crackdown on theft, fog technology is designed to deter break-ins after hours, and has been around for some time.

The machines — which are present in some, but not all stores nationally — are designed to go off automatically when a store is broken into after closing time. But a technical mishap caused it to be deployed with shoppers present on Friday night at around 10.30 pm. Thankfully, there is no health risk associated with the fog technology.

Some people on social media, seemingly familiar with the tech, suggested a malfunction was to blame. "I genuinely had no idea that they used them at grocery shops," the poster said in response.

Front of Coles supermarket store
Coles has rolled out a number of anti-theft technologies across its stores. Source: Getty Images

Coles ramps up anti-theft measures

Earlier this year, the supermarket announced it would be taking more in-store security measures to address the ongoing issue of "hundreds of thieves" being caught every week in its stores. Coles has recently rolled out a wide range of anti-theft technology to stop shoppers from stealing.

"Coles has a range of security measures in place to reduce theft from our stores including CCTV, electronic article surveillance (EAS) and in some stores, new smart gate technology that automatically opens as customers make payment for their products," a spokesperson said at the time.

"Additionally, trolley lock technology has been in place at a number of our stores in recent years and this technology uses sensors to prevent trolleys leaving the store if someone hasn't first paid at a register. Some of these security measures are trials at this stage, and we are keen to hear what our customers think of the new technology before it is rolled out further."

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