Police have urged people to keep their dogs on leads after five sheep were killed near York.
It follows two separate attacks on a farm in Wigginton.
The first attack, two weeks ago, left three pregnant ewes dead. And last week another two pregnant ewes were savaged to death.
All of these sheep were in the same field that has a public footpath along the edge.
The stress of being chased may also have resulted in more of the remaining 300 ewes terminating their pregnancies. The lambs are due in early April.
Police released the above picture of one of the sheep – saying other images are too graphic to publish.
PC Jack Donaldson of the Rural Task Force, said: “It is a constant worry for farmers when unrestrained dogs have the capability to kill and wound large numbers of animals in a single attack.
“Nobody wants to see animals suffer in this way, and there should be no excuses for not having your dog under proper control.
“We urge dog owners to act responsibly when walking in the countryside. Keep your dog on a lead at all times. Do not let your dog trespass onto private land.”
Sheep worrying is a criminal offence. Simply allowing your dog to be out of control around livestock is a crime.
Not only will owners face prosecution if their dog is out of control, but they also run the risk of their pets being shot.
A North Yorkshire Police spokesperson said: “As a last resort, if a farmer believes a dog is an immediate danger to their livestock and there are no other reasonable means to protect their animals, your pet could end up being shot by a farmer.”