The scams see people receive a call from someone claiming to be a police officer alerting them to fraudulent activity on their account and asking them to assist with their investigation.
They convince the caller that they are genuine, then ask the victim to visit their bank or bureau de change to withdraw pounds or euros, which can be collected by the scammers.
Officers are asking people to look out for vulnerable friends, family or others in the community who may be at risk of becoming a victim.
Detective Inspector Craig Gilmore said: “Enquiries are being carried out by a team of specialist officers to identify those responsible.
“I would like to highlight this scam and ask people to be vigilant. I urge anyone who has an elderly relative or neighbor to inform them of this type of scam.
“Police officers or your bank will never ask you to transfer money to another account or withdraw money from your account. They will never ask you to disclose personal financial information.
“These callous criminals prey on the most vulnerable people in our communities. They go to great lengths to appear legitimate, including having your personal information.
“In some cases, victims, thinking they are helping a police investigation, are left extremely upset and worried when they realize they have been the victim of a scam.
“If you receive a call of this nature, do not engage the caller and hang up. This is a scam. If you’re not sure, take a few minutes to think about it. Write down the caller’s phone number, hang up and contact the police on 101.