Police have issued a warning over men claiming to be former prisoners who are cold calling at homes in Norfolk. 

Officers have posted the warning after a series of calls from victims in Caister, Acle and Blofield.

The reports came on Wednesday after men went door to door trying to sell various items out of a bag, claiming "they have recently been released from prison and are trying to make some money".

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The technique known as 'Nottingham knockers' is often used by criminals who can sometimes turn aggressive towards victims when they refuse to buy anything.

If anyone is met with agitated cold callers, police have advised locals to lock their doors before answering the door and "to consider only speaking to them through a closed, locked door, if at all".

"Tell them you are not interested and ask them to leave, despite any persistence," they added. 

"We would always advise you not to agree to buy goods from, or have work done, by anyone who calls unannounced or approaches you in the street."