A large amount of documentation and bank cards were seized along with a small quantity of ammunition during one of the searches.
Two women, aged 37 and 26, and a 37-year-old man were detained on suspicion of a number of offences including conspiracy to commit fraud, conspiracy to commit blackmail, acquiring criminal property, converting criminal property.
The man and one of the women were also arrested on suspicion of possession of ammunition in suspicious circumstances.
Detective Chief Inspector Ian Wilson said: “The searches and arrests follow several reports of a male contacting a number of victims by telephone under the guise of being a police officer.
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“In the majority of these calls the male would inform the victims that their bank accounts had been targeted by fraudsters and that an officer would call with them.
“The victims were asked to withdraw money to enable the officer to check if it was real or fake when he called. Thankfully no money was lost by any of those contacted and no-one called to their homes.
“On one occasion however a man aged in his 70s was contacted by a male claiming to represent British Telecom who persuaded the victim to transfer money to an account the fraudster had given him details of. In total over £2,000 was taken.
“Financial institutions, utility companies, law enforcement, HMRC, internet and telecoms providers will never ask you to transfer money because your account is compromised or call out of the blue and ask for remote access to your computer or to download software.
“Our enquiries are still ongoing and I would ask anyone who has been contacted in similar circumstances recently to report the matter to us on 101.
“Further advice and information can also be obtained by visiting www.nidirect.gov.uk/scamwiseni or the ScamwiseNI Facebook page @scamwiseni.”