Police in Derry and Strabane say they have received reports of scam activity, including one incident where £20,000 was lost.
The fraud appeared to be a genuine business investment, but was in fact a scam.
The PSNI is warning the public that scams come in many different forms, with some made to look completely legitimate.
People are being urged to stop and check who they are communicating with before handing over any money, and to ask themselves whether an offer looks too good to be true.
The PSNI says investment scams can often appear to be a way of boosting savings, but may involve high-risk investments with limited regulation or safeguards.
Anyone who has lost money or been targeted by a scam should report it to Action Fraud, contact police on 101, and notify their bank immediately.
Suspected fraudulent texts can also be forwarded to 7726.
