The incident, in which the 45-year-old victim was persuaded to hand over a significant amount of cash, began on 25 March when a black man approached him in the BD7 area and offered to buy his car.
The victim exchanged details with the man and agreed to meet him at a business park in Canal Road on 29 March.
At the meeting the victim was offered ‘gems’, which he was told were worth around £40,000 and would need to be sold before the car could be purchased.
The victim agreed to purchase the items for a discounted price and the cash was handed over.
The gems, which were referred to as ‘Blue Gold’ have been found to be fake and police are now warning the public to be aware of this scam.
PC Toni Hinnells, of Bradford District CID, said:
“While we are only aware of one report of this type of fraud so far this year, we are aware that a similar scam has previously operated in the Bradford and Huddersfield areas.
“It is possible that these men are part of a larger group, who are targeting individuals to gain significant amounts of cash through deception.
“We want people to be fully aware of the potential tactics being used by these criminal enterprises and to report those behind it.
“If it appears too good to be true, it is most likely that it is.”
Anyone who has information about this incident or who can identify these men is asked to contact Bradford District CID, quoting crime reference 13170144170.
Information can also be given anonymously to the independent charity Crimestoppers on 0800 555 111.