Farmers are being urged to join the Farm Watch scheme following the theft of four sheep, believed to have been killed for meat.
The animals were stolen in Goole and their skins were found dumped in a field, but police officers are urging all farmers in the region to step up their security.
Farm Watch is a network of farmers and police officers who share information about incidents .
Members also receive crime prevention advice to help reduce the risk of them becoming victims.
A Humberside Police spokesman said: “Officers have made enquiries into this incident but as there is little forensic evidence remaining.
“Enquiries have been concluded without a suspect being identified.
“Local residents in our rural communities face very different challenges to our urban residents and as such we offer support and advice wherever possible.
“We also advise farmers to join Farm Watch Schemes and share their experiences and receive support and local information about activities in their areas.
“Whilst there is still less crime in rural areas than in urban settings, when crime does occur it has a major impact on the victim. It can also create a fear of crime in isolated rural locations
“The message we want to put across is that while rural crime does occur, these areas are a safe place to live. There is less criminal activity there than in urban areas, just different challenges we have to face.
“Humberside Police would like to ask residents, whether from the farming community or not, to keep their eyes open and report anything suspicious.”
The force urged farmers to check on livestock regularly to try to prevent any rustling.
A force spokesman added: “Check the security of boundary fencing and hedging and make regular checks of fields where animals are kept to ensure fences are not breached.
“Use ear tags, horn brands, freeze marking or tattooing to made animals easily identifiable.”