Police in the county are appealing for information after receiving three reports of dog thefts since 15 December, half of which were pedigree cocker spaniels.
In the first incident, three pedigree cocker spaniels were taken from kennels in North Molton between 9am and 5pm on 15 December.
One was a female, seven-year-old black Devonshire Faith spaniel, the second, an 18-month-old black Hillside Harriet female with a white bib, and the third dog was a gold Badgeberry Troufseau Hope spaniel.
On the same day, also in North Molton, between 7pm and 9pm, a cocker spaniel called Ivy was taken from the rear garden from her kennel.
She was found dead at Bommertown Cross at approximately 8am the following morning.
In the third incident, at around 10am on 17 December, a female chocolate brown cocker spaniel and a female black and white spaniel were reported missing from the South Molton area.
Investigating Officer PC Steve Theobald said: "We are very concerned about the welfare of these dogs and urge the public to come forward with information.
"The owners are all aware of the incidents and are understandably shocked and upset by this.
"Enquiries are ongoing to locate the suspect/s and we are currently looking through CCTV.