The head of the Garda National Economic Crime Bureau has said in the last three days, over one hundred amounts ranging between €2,500 and €19,500 have been reported stolen by people as a result of "smishing" or fake text messages.
Speaking on RTÉ's Drivetime, Det. Chief Superintendent Pat Lordan said the automated calls aren't as convincing as the text messages.
Mr Lordan said the majority of these voice calls are coming in from foreign carriers and are disguised as 085, 086 and 087 phone numbers, as numbers from Garda stations or Government departments.
He urged phone companies to filter these calls, identify the source and try to work with Gardai, Interpol and Europol to try to stop this.
He said people have done nothing wrong by answering these calls, but urged people not to engage in conversation with them or share any personal information with them.
Mr Lordan said in one recent case, a person was on the phone for one hour while he was being persuaded to transfer money from his bank account.
He urged people not to respond to the text companies.
Meanwhile, Bank of Ireland has issued a new warning to the public to take extra caution around fraudulent text messages in circulation this week.
The bank has noted a spike in "smishing", where fraudsters send fake text messages - which appear to come from Bank of Ireland - and direct customers to fake websites imitating Bank of Ireland websites.
Since last month, Bank of Ireland said the number of new 'phishing' websites detected by its Fraud Prevention team has doubled.
It also said it has seen an unprecedented increase in activity in the last week, with up to 20 new fraudulent sites appearing a day.
Bank of Ireland is advising customers not to click on links or to respond to SMS text messages, which are designed to appear as if sent by the bank and look like originating from a genuine phone number.
The bank said it will never send customers a text with a link to a website that asks for online banking login details or any one-time codes that have been sent to customers.
Edel McDermott, Head of Group Fraud at Bank of Ireland, said that May and June are showing a worrying upward trend in activity.
She said the bank was seeing an almost three-fold increase in the number of customers being targeted by fraudsters.
"The potential financial impact is even more stark, with fraudsters attempting to defraud close to five times more money than in the same period in 2020," Ms McDermott said.
"Our teams are working hard to respond to these spikes and intercept fraud attempts but unfortunately, if customers click on links and provide personal banking details, recovery is not always possible," she added.
The lender has also asked customers that if they get a suspicious text please, to email a screenshot of the text to 365Security@boi.com and then delete the text.
It also said that if a customer thinks they may have given away any of their banking details to call the bank's 24/7 Freephone line 1800 946 764 immediately.