Detectives have warned people living in Sheffield to be vigilant following a seventh incident where a conman pretended to be a police officer.
The warning comes after a man, described as white and aged around 30, attended the address of an 88-year-old man in the Gleadless area at around 12.10pm on Friday.
He claimed he was a police sergeant and needed to see how much cash was in the house.
Det Insp Steve Smith said: "The 88-year-old absolutely refused entry to him which was the right thing to do, even though the man was incredibly persistent, he would not let him in until he had made further checks and the man left when he wasn’t able to gain entry.
“Detectives in Sheffield are investigating this incident, as well as six previous incidents earlier this month across the city in Hillsborough, Gleadless, Totley, Woodhouse, Broomhill and Heeley.
“I would like to offer my reassurance that a thorough investigation is already underway and we are pursuing a number of lines of enquiry to identify the offenders responsible.
“I do understand this will cause concern to our local communities, and I would advise residents to please be assured that all of our officers carry photo warrant cards, which will always be presented to members of public they are visiting.
“If you remain unsure, or believe the ID presented isn’t legitimate, please call 101 who will be able to confirm an officers details. Our officers are more than happy to wait outside while you make as many necessary checks as you need.
“A police officer will also never make demands for cash. If officers are attending a property to seize items or money, they will have a valid search warrant which will be presented before entry and the relevant legislation will be referenced.
“Please share this information with family and friends and for all our residents in South Yorkshire, if anyone calls at your home purporting to be from any organisation or company, if you’re not sure, don’t open the door.”
Anyone with any information about the incident should call police 101, quoting incident number 375 of May 11.
Alternatively, call Crimestoppers, anonymously, on 0800 555111.