A man phoned the county force control room to report that his drug dealer had short-changed him.
Busy call handlers in the Wootton Hall FCR took the bizarre complaint from a man calling from Northampton at about 6pm on Wednesday, October 23.
Inspector Carl Wilson tweeted: "Just when you think you have heard it all, a male called in to Northants FCR overnight to complain that his drug dealer short changed him!"
A force spokeswoman said that the intelligence would be passed on to the relevant department, adding: "We would remind members of the public that this is obviously not an appropriate use of our time. We need to keep our staff free to speak to people who are in genuine need of help.
"The vast majority of callers use the system sensibly but there are a few who do not."
You can phone 999 in an emergency or 101 in a non-emergency. If you have intelligence about a crime but you wish to remain anonymous, you can phone Crimestoppers on 0800 555 111.