An advertising watchdog has launched an investigation into vaping promotions on Instagram following Telegraph findings.
The Advertising Standards Authority confirmed it was looking into three posts over whether they had featured underage young people.
The body is also investigating whether the e-cigarettes involved in the promotional posts are permitted to be advertised on social media.
The move comes a month after the Telegraph revealed that vape products with cartoons on were being promoted to children as young as 13 by Instagram's suggested posts feature. Since 2016 it has been illegal to sell e-cigarettes to under 18s in the UK.
The investigation also found that some vape shops and businesses appeared to be using young ‘influencers’ with large Instagram followings to run promotional posts for their e-cigarettes and products. These promotions were not official Instagram adverts, but instead sponsored posts that also fall under advertising regulations.
ASA rules state that people featuring in e-cigarette advertisments “must neither be, nor seem to be, under 25”.
A spokesman for the ASA said: “We have now launched formal investigations into each of the ads. We will publish our findings in due course.”
John Dicey, the CEO of Allen Carr's Easyway smoking cessation clinics, warned that promotions featuring young people could project a “sexy, young, aspirational view of vaping” to an underage audience.
He said: “It’s really taking the place of the old cigarette adverts in 1950s, 60s, and 70s, using the exact same techniques.
“Youngsters believe e-cigarettes are not particularly harmful or addictive, but they always aspire to move on to the next level - the inclination is to move on to the "hard stuff" - cigarettes."
In recent years e-cigarettes have been seen as a less harmful alternative to smoking, with some experts arguing they should be made available on prescription to people trying to quit.
However, a report from Public Health England earlier this year also showed that the number of children and teenagers trying vaping has doubled in five years.
Around one in six children aged between 11 and 18 has tried e-cigarettes, with many saying they liked the flavours.
John Dunne, a board member of the UK Vaping Industry Association, said it was working with members to ensure they complied with advertising rules.
He added: “It is wholly inappropriate for a nicotine-containing product to be marketed in a way that might appeal to children.
“Responsible vaping businesses, who make up the vast majority of the industry in the UK, would not condone such behaviour”.