The State communications regulator has issued a warning to the public after a spate of scam calls from international numbers.
ComReg has warned that returning calls from unfamiliar international phone numbers could end up costing you a fortune.
People around the country have been getting missed calls from far-flung countries including Liberia, Chad and, in the past few hours, the island of Comoros.
The calls usually only last for a couple of rings and often come through during the night or in the early morning.
Anyone who decides to return the call could be liable for huge charges at international premium rates.
Some of those taken in by the scam have reportedly been greeted by a voice answering service, attempting to keep callers on the line for longer.
Please see ComReg's advice on scam calls at the link below: https://t.co/Gs4Oorlxtq
— ComReg (@comreg) October 18, 2017
On Newstalk's Moncrieff this afternoon, ComReg public affairs manager Tom Butler said there is an easy way to avoid being scammed:
"When the number comes up, if you don't recognise the number let it ring out," he said.
"If it rings out after one or two rings, it is most probably a scam call.
"If it doesn't leave a message for you to ring back [...] unless there is a genuine reason to ring the number back - don't ring it back."
He said anyone with a family member or friend living abroad should store their number in your phone and be aware of the prefix for the country they are calling from.
He also advised people never to give out bank details or personal information over the phone.
Anyone who is consistently receiving missed calls from unknown numbers should contact their phone operator.
"What we are saying to people is prevention is the best cure," he said.
"If you know a number or know someone is contacting you for a genuine or Bona Fide reason, they will leave a message.
"If you are ringing back anybody who you haven't dealt with before obviously you don't give any personal details - those rules still apply.
"People should just think before they return the call."
You can listen back to Mr Butler's conversation with Sean Moncrieff here: