By bizn_fun 
A spokesperson for Tesco said they have a “robust set of technical and operational measures” in place to prevent and deal with card tampering.
They advised customers to check gift cards carefully before they buy and to speak to the customer service team if they think they have been victims of fraud.
Amanda Wolf, head of Report Fraud, said under reporting made it difficult to know exactly how much it was increasing by, but said their intelligence suggested cases had risen by about a quarter over the past two years.
“It’s not unusual when there’s an emerging crime type,” she said.
“But it’s absolutely one we are looking at and we are looking to do a deep dive into over the next 12 months.”
She said most of the reports come in around January after the festive period.
The ways people are caught out include buying fake online gift cards, accidentally buying a card which has been tampered with or being tricked into buying gift cards for someone.
She also said criminals use phishing emails offering fake gift cards as a prize or a deal.
Ms Wolf said: “Make sure you’re buying from reputable sellers, if you’re purchasing in person make sure it’s not been tampered with.
“If they look poorly made, or don’t have visible security features, don’t use them and take them back.
“Use two-factor authentication (when shopping online) and check out as a guest to protect your details unless it’s a website you recognise and use regularly.
“For that 30 seconds, stop, and think.”
She also said she would like to see gift cards being better protected in shops, including being put behind the till.