Scams and cold callers are becoming more of an issue as opportunists prey on the most vulnerable.
The last year alone has seen a huge increase in fraud, which mainly originates from social media, online marketplaces and dating apps.
Now, a cyber-security expert has revealed the three phrases which you should watch out for when called by an unknown number.
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One particular concern is a rise in complaints about fraudsters masquerading as legitimate retailers, or the rise of scams on WhatsApp, such as the notorious "hi mum, hi dad" con.
Dr Klaus Schenk, head of product security at the software company Verimatrix, has now given some advice on the "warning signs" that should indicate when something is wrong on a cold call. He said the first thing to watch out for is a call from an unknown number, as well as three particular phrases.
Dr Klaus told The Sun: "Be wary if the caller asks for immediate payment or requests you to disclose personal information. Promises of lucrative financial opportunities or gifts, along with emotional manipulation tactics, should also raise suspicion. Thirdly, you should be very cautious when anyone on the phone asks you to "install an app".
"Similarly, if the caller insists on installing certain apps or demands a comprehensive set of personal details, it is advisable to exercise caution", Dr Klaus added.
His comments come after consumer finance expert Martin Lewis issued a warning over a "disgraceful" deepfake scam advert for an investment app.
The broadcaster said people are using technology to "pervert and destroy" his reputation in order to scam people online. The advert, which reportedly circulated on Facebook, appears to show Mr Lewis endorsing an Elon Musk-backed investment scheme through a video at his home.
"Musk's new project opens up new opportunities for British citizens. No project has ever given such opportunities to residents of the country", the fake Mr Lewis says in the footage.
But the clip is AI-generated, using deepfake technology to replicate the expert's face and voice using existing video and sound, making it appear realistic.
"It's pretty frightening," Mr Lewis told the BBC. "These people are trying to pervert and destroy my reputation in order to steal money off vulnerable people, and frankly it is disgraceful, and people are going to lose money and people's mental health are going to be affected."
He said it was the first time he has been used in this sort of video scam.
Mr Lewis, who founded Money Saving Expert and has around 2.3 million followers on Twitter, said more needs to be done to regulate scam adverts and protect victims of financial crimes.
Meta said it is investigating after claims the Martin Lewis video appeared for users on Facebook.
