A Russian photography student has carried out an experiment to show how easy it is to identify complete strangers.

Twenty-one-year-old Egor Tsvetkov took photos of people in public places and then tracked them down on the Russian social media site VKontakte using a facial recognition app.

The experiment 'Your Face Is Big Data' was published online and has been viewed more than 70,000 times.

Video journalist: Anne-Marie Tomchak

Producer: Emma Wilson

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