Police are urging residents to be cautious of unofficial door-to-door sellers, after a spate of incidents.
The Force is aware of an organised practice where a group is dropped off by a vehicle in different locations to sell their goods.
Neighbourhood Sergeant Sharon Wilmore-Greaves said that these people tend to be from the Middlesbrough area, are ex-offenders and sell goods from holdalls.
Incidents have occurred in areas such as Alnwick, Rothbury and North Broomhill and Sgt Wilmore-Greaves said the sellers can get aggressive towards people who aren’t interested.
She added that there have been occasions where subsequent crime has occurred without explanation.
Residents are urged to ask to see some identification and the seller’s valid Police Peddlers Licence or Traders Licence, and then contact police so officers can verify the person’s identity and gather intelligence. Call police on 101.