The P.S.N.I. has issued an urgent fraud warning after a member of the public fell victim to scammers selling fake smartphones.
The incident occurred in Coleraine recently and local P.S.N.I. officers have launched an investigation.
The same plays out when a fraudster offers a high-spec mobile phone in exchange for money.
The phone at the beginning of the scam is genuine with scammers encouraging would-be victims to insert their own personal sim-card to prove that it works.
However, once the would-be victim has finished checking the phone the defrauders swap the genuine phone with a counterfeit device.
It's only when the fraudster leaves that individuals realise they have handed over cash in exchange for a counterfeit device.
"If you are offered the latest mobile phone at a price that is too good to be true, ask yourself why it is so cheap?," advised the P.S.N.I.
"We are aware of similar incidents in other places so help spread the word and make sure you aren’t caught out."