The sheep farmers fear the sheep have been shot and then stolen, reports broadcaster NRK.
Farmer Sivert Svane, who has lost three of his flock, told the broadcaster that he had reported the suspected thefts.
“Last Sunday I heard a lot of noise that suggests someone has been in to take the animals. Shots have been heard in the area,” he said.
The fence around Svane's property was intact but the animals had disappeared, he told NRK.
“We have reported it to the police, and they said they were interested in following developments,” he said.
Svane is not the only farmer to have had sheep vanish.
Farmers on Aust-Agder's archipelago have seen their sheep ‘fished' away using fishing equipment, the farmer told NRK.
Another farmer from the area told the broadcaster that he had recently found a sheep with its legs bound for transportation, as well as a lamb with a large fishing hook attached to it.
“We have found several animals with fishing hooks in their wool… This is clearly a deliberate action by people,” Jens Eide, a butcher from Lillesand, told NRK.
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Several farmer owners in the area have reported animals to have disappeared with any natural explanation, Svane said.
The leader of the local association of sheep and goat farmers said it was “concerned” about the disappearances.
“This is very unusual for us, but we are hoping the police will take care of it,” Kåre Blålid told NRK.
Sheep theft in Norway is not a new phenomenon.
70 animals were stolen from a flock in Jæren in 2010, while man in his 40s was arrested earlier this year for stealing 20 sheep in the Hemsedal region, reports NRK.
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