Welfare cheats are resorting to wearing fake beards and make-up in a bid to claim benefits, Social Protection Minister Leo Varadkar has said.
The minister is calling on people to blow the whistle on friends or neighbours who they suspect are taking State money which they are not entitled to.
He is considering a new 'name and shame' approach to people who are convicted of welfare fraud.
Mr Varadkar launched a campaign yesterday to raise awareness about the level of fraud in the system, saying: "The only way we can act on it is through the control measures we already have in place and through people giving us tip-offs."
He said his officials have lots of "different tools" for identifying fraud and monitor social media sites such as Facebook and Twitter to catch people out.
In particular the minister said the introduction of the public service card, which around 2.5 million people now have, has made "a big difference".
Mr Varadkar said the facial recognition technology associated with the card was helping the Department of Social Protection find "doppelgangers" who try to double claim payments.
"There are quite a few out there," he said. The facial recognition software can identify 'double people' out there.
"Even people putting on make-up and beards and stuff.
"None of that works because it's all based on bone structure."
Asked which payments are most targeted by cheats, Mr Varadkar said they tended to focus on shorter-term benefits.
"It's impossible to estimate for sure how much fraud is happening," he said.
"Obviously for some schemes like pensions and child benefit it's very low, but for others it's much higher."
Three times a year his officials do a random survey of around 1,000 claims under different categories to check for fraud. In the coming months this process will target those illegally claiming carers' benefit.
"We're also considering new penalties such as being able to name and shame people who are prosecuted, and having a register of that," he said.
"It doesn't happen now. It's something that's quite easy to do.
"What we're considering doing is putting up on a quarterly basis a list of people prosecuted and convicted of welfare fraud."
Last year 20,800 allegations of social welfare fraud were dealt with by the department.
The majority of public reports in 2016 concerned Jobseeker's schemes, Supplementary Welfare Allowance and One Parent Family Payment.
The most common reports allege issues such as working while claiming, cohabiting with a partner who is making a financial contribution, or claiming while living abroad.
The department estimates that approximately one-in-three reports results in a payment being reduced or stopped.
Some 194 were referred to the Chief State Solicitor's Office for proceedings to issue. A further 160 cases were referred for prosecution to the DPP.