Ryan Tubridy has threatened to take legal action after his face was used for scam ads selling cryptocurrency.
The RTE presenter took aim at the criminals using his likeness on his morning radio show on Thursday.
His warning comes after a top Garda told the Irish Mirror that a woman had lost €1,000,000 in an investment fraud scam.
READ MORE: Irish woman loses €1m in dangerous scam as top Garda superintendent warns of cryptocurrency fraud
Ryan said: "Yet another person stopped me yesterday on the street. I'm on Instagram, I like being on Instagram. I was walking yesterday and someone told me that my face kept coming up in ads for cryptocurrency.
"I want to make this abundantly clear this morning. I have nothing to do with these ads you see. Not one thing. This is a scam. We are living in generation scam. The internet is alive and thriving with cruel scams
"Unfortunately. the difficulty is it's like whack-a-mole - as soon as they get rid of one, another pops up. The truth is - do you remember that 'I don't know what a tracker mortgage is'? I don't know what cryptocurrency is. It sounds like something from the Simpsons: Monorail, monorail, cryptocurrency, cryptocurrency. I have nothing to do with it.
"They're clever, they use a screengrab, it looks professional, we're trying to get rid of them. What I don't like about these gangsters is that they're stealing. People have lost millions in crypto fraud.
"I suspect Miriam O'Callaghan, when she won her case recently, it was along these lines. I admire her for taking the case because it is costly in terms of time and energy. She won the case and I may not be far behind her if this continues, because it's too much."
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