Scam emails purporting to be from members of the clergy, including the Archbishop of York, have been sent to church officials.
The emails ask church wardens and volunteers in the Anglican Diocese of York to reply but not to call.
Victims are asked to purchase online gift cards as a thank you present for members of the church community.
North Yorkshire Police said anyone receiving an email should check the sender address and not make a purchase.
The force said the fraudulent emails read: "Do you have a moment I have a request I need you to handle discreetly. I am currently busy in a prayer session, no calls so just reply my email."
Once an email conversation begins, the scammer asks the targeted individual to buy vouchers online and provides reassurances that the money will be reimbursed.
They then ask the victim to send photos of the vouchers which allows them to collect the unique codes and use them to make online purchases.
North Yorkshire Police said anyone receiving an email should report it and the Diocese of York has also issued a warning to staff.