20 police reports have been received about a County Donegal scam involving a holiday home.
A fraudulent Facebook Marketplace advertisement convinces people to pay a deposit in order to book a vacation home that they don't own.
Police believe that more people have been scammed since May's revelations.
Suspect Gerard Pollock encouraged anyone who came across the fraud to report it the PSNI.
BBC News NI interviewed a County Tyrone woman last month about being conned into paying PS200 for booking holiday accommodation with her mother.
Supt Pollock spoke to BBC News NI's Evening Extra and stated that "our enquiries would indicate that these ads have been noted by as many as 500 people."
"These are the people we think have seen these ads and may have considered them."
Supt. Pollock stated that the deposit amounts for the Donegal scam could range from PS100 to PS500.
The police are also aware that there is a similar online scam. Four reports were made about bogus Portrush holiday accommodation.
Victims have made deposits between PS100-PS200. This is similar to the Donegal scam. Once deposits are made, they do not hear from anyone.
