Sixteen lambs were killed and another four were injured after being attacked by at least one dog in Fife.
Six lambs were found dead on a farm in Kelty and a further 10 were so badly injured they had to be euthanised, police have said.
The incident happened at Blairadam Farm between 10.30am and 1.30pm on Monday.
The attack is estimated to have cost the farmer about £7,000.
Local police are appealing for anyone with any information to come forward by calling 101 and quoting incident number 1580 of Monday April 3 2023.
Scottish Land and Estates have urged dog owners to keep their dogs on a leash when walking them near farmlands.
Simon Ovenden, policy adviser at Scottish Land & Estates, said: “Dog-owners and walkers should not take a dog into fields where there are lambs, calves or other young animals and should always keep their dog on a short lead, under close control.
“Dog walkers should also try to stay as far away from livestock as possible – even aggressive behaviour from a dog such as barking can cause a pregnant sheep to die or miscarry.
“Such incidents are not the dog’s fault, but that of the owner, and declaring that a dog has never acted in such a manner previously is of no importance when dealing with the aftermath of an attack on livestock.
“Dog walkers should enjoy rural Scotland but with care and caution practised at all times.”
Inspector Stephen Gray, of Police Scotland, said: “Inquiries are ongoing to establish the full circumstances of the incident and we are appealing to anyone with information to come forward.
“The lambing season has started and worrying can cause stress to sheep that can result in them losing their lambs, as well as injuries that can lead to their death.
“All of this is at considerable cost to farmers.
“Dog owners could face prosecution if their dog attacks livestock so we are urging them to keep dogs on a lead when walking near livestock as well as making sure they do not run or escape into fields on their own.
“I am asking all dog owners to be considerate. Please remember that it is your dog and your responsibility to keep them under control.”
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