Thousands of children are betting millions of pounds on the outcomes of matches played by professional video gamers on unlicensed gambling websites.
The teenagers are using "skins" as a virtual currency, which can be won or bought in game and act as cosmetic upgrades to a player's character, such as camouflage for a gun or a new suit of armour.
More than £5 billion worth of "skins" were bet globally in 2015,
The Times reports.
The virtual currency is then bet on the outcome of matches between gamers in "eSports" competitions in games such as
Counter-Strike: Global Offensive,
Dota 2 and
League of Legends.
One website, CS:GOLounge, reportedly took more than £800 million in "skin" bets last year. Five per cent of traffic to the Costa Rica-based site came from the UK.
A third third of its visitors were under 18, suggesting British children bet more than £12 million on the site in 2015.