Police are warning residents to be extra careful following a series of bogus callers offering roofing work.
Officers believe the five incidents, which took place across Hartlepool, Middlesbrough and Stockton, are linked.
Cleveland Police received reports of incidents on Monday, February 26, in Stillington, on Monday, March 5, in Seymour Crescent in Eaglescliffe and Coatsay Close in Hardwick.
On Wednesday, March 7, there was an incident in Dunstable Road in Middlesbrough and on Thursday, March 8, on Catcote Road in Hartlepool.
As a result of these incidents, several hundreds of pounds have been stolen from elderly victims for work which has not been carried out.
One of the male suspects is described as having a ginger beard and is believed to be aged in his late twenties.
Officers would ask members of the public to remain vigilant with cold callers and to only open the door to people if they feel comfortable. In order to verify identification, people can call the company concerned.
Any witnesses or anyone with information regarding the incidents is asked to contact Detective Inspector Louise Sproson from Stockton Operational Crime Team on the non-emergency number 101 or Crimestoppers anonymously on 0800 555 111 or www.crimestoppers-uk.org.