Detectives are investigating an internet scam over the sale of fake tickets for two forthcoming shows.
The shows in question are Adele in Belfast and Justin Bieber in Dublin.
Police believe tickets being sold in groups of four on the gumtree website are fake.
A man has been arrested by the PSNI in Strabane and interviewed. He has since been released pending further enquiries.
Detective Inspector Lyndsey Kitchen said: “As part of this ongoing investigation we want to ensure that we identify as many people as possible who may have been victims of this fraud.”
Money has changed hands in face-to-face transactions with a man. But police believe the tickets to be fake.
They want to hear from anyone who may have purchased tickets in a group of four from a man using gumtree.
Anyone who has should contact the PSNI in Strabane on the non-emergency number 101.
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