POLICE have warned of sophisticated scammers that pretend to be from Visa or Mastercard.

In an online alert, PCSO Ahmed Mohamed said they were targetting landlines asking for an international transaction of £600.

He warned victims to 'stay vigilant' and not to reveal personal details.

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He also said that scam is the number 1 crime in the UK.

In an emergency call 999.

To report a scam to police go online or call 101.