Residents in north Norfolk have been warned to be on their guard after reports of cold callers contacting people about 'insulation and roofing' as they are 'working in your area'.
Police said people should also be 'very wary' of any approach made in a telephone cold call.
A spokesman said: 'Never give or confirm any personal details or agree to someone visiting your home if approached in this manner.
'We also advise when looking to have work done on or around your property only deal with reputable companies you have researched and chosen yourself and have obtained a written quotation from.'
Anyone wanting advice about cold calling, or anyone who has agreed to a visit during a cold call, should contact the Citizens Advice consumer helpline via their online reporting form or call 03454 040506.
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