Conmen posing as engineers selling solar panels tricked a vulnerable elderly man out of money in Heckmondwike.
The incident happened at around 3pm on Friday, February 10, when the two men approached an address on Fairfield Road in Heckmondwike.
They spoke to the occupant, a vulnerable man in his 70s, and told him he was due a refund.
They produced a card machine, and stole a large sum of money.
Both suspects are described as Asian and both were smartly dressed.
The first suspect was around 5ft 8ins, stocky, athletic build, and between 25 and 35-years-old.
The second was 5ft 11ins, of slim build, and aged between 26 and 28-years-old.
Detective Constable Rob Rutherford of Kirklees District CID said: "Clearly this incident has been very distressing for the victim. I would like appeal to anyone who may have been in or around the area on Friday afternoon and may have seen anyone matching the suspects descriptions, or acting suspiciously to speak to the police.
"I am keen to establish details of any vehicle they were using, Our enquiries into this incident are very much ongoing.
"Anyone who may have any concerns about people approaching their home, or that of a family member or friend are always encouraged to check a person's identity and to contact the company they claim to be from. Use a number from a trusted source, such as a list by the telephone, or one looked up from a directory.
"Do not use the number given by the caller. Close the door to make the call. Some gas, water and electric companies offer a password system for older or vulnerable customers to offer reassurance. If you have any concerns about the person at your address contact the police. Any legitimate caller will be understanding of your concerns."
Anyone with any information is asked to contact DC Rob Rutherford at Kirklees CID via 101, quoting 13170065347. Information can also be passed anonymously to the independent crime fighting charity Crimestoppers on 0800 555 111.