The owner of a rare breed of sheep, believed to have been killed six weeks before giving birth, has appealed to the public for information.
Marian Whittaker, of Kinsbourne Green Lane, Harpenden, said she was devastated after her sheep, Jill, is thought to have been killed between 4pm last Thursday and noon the following day.
Police said the killers are thought to have broken through a fence and into a field where the sheep was being kept.
A pool of blood was found in the field and it is believed this is where the pedigree Greyface Dartmoor sheep, which was due to have twins, was killed.
Criminals then removed the body from the field before leaving in a vehicle in an unknown direction.
The 54-year-old owner said: "I'm devastated to lose Jill. She was a placid, friendly ewe who was no trouble at all. She produced two nice lambs each year and mothered them well.
"She was only six weeks away from giving birth and the lambs will just have been wasted. Who would kill a pregnant mum like that?
"My business is only small and I have worked hard to build up a loyal following of customers who like my locally produced, welfare-friendly meat and look forward to their lamb box for the freezer.
"The loss of two lambs is serious for my business and I hope I don't have to disappoint would-be clients this summer."
The investigation is also being supported by the Constabulary’s Rural Operational Support Team (ROST), who specialisein dealing with crimes concerning rural and agricultural issues, wildlife, the local environment and the county’s heritage.
PC Jane Flemons said: "As you can imagine, this terrible incident has caused the owner a great deal of distress and we are doing all we can to identify those responsible.
"The outcome of this crime is particularly sad as the sheep was pregnant with two lambs.
"This particular type of sheep is quite rare. If you were in the area during the stated times and saw anyone acting suspiciously, please get in contact as soon as possible."