Gardai say criminals are using some dead people's bank accounts as part of online scams.
They're warning about a rise in cyber crimes, which are becoming more sophisticated to try and catch people out.
There were 24 thousand suspicious transactions last year - twice the number there were 5 years ago.
Gardai say many online scams are becoming harder to spot but that they're putting extra resources into tackling cyber crime.
Recent ones included fake Electric Picnic tickets and iTunes gift cards.
Detective Chief Superintendent Patrick Lordan explains how businesses are being targetted:
"they normally do it when your CEO or head of finance is away on holidays or away at a meeting, they're constantly watching social media [for that] it's their full time job"
Businesses and consumers are being advised to double check anything they're not sure about.