Graphic content: Barbaric attack on spring lambs in County Londonderry

And Feeny farmer Gerald McLaughlin says he and his family have been traumatised by the attacks which have been happening since 1992.

Over 500 sheep have been attacked in that time and have all had to be put down.

“It is absolutely horrific, there are simply no words to describe it,” said Gerald who has a 300-strong flock of sheep, just outside Feeny.

For several years, questions remained on whether the attacks were carried out by a human, or possibly by wildlife - birds or a fox.

But Gerald and his wife Bridget say there can be no doubt, that it is a person responsible for the hideous crimes.

The Sentinel has read a letter from the USPCA dated from 2008, which confirmed they were investigating the attacks.

“Since this all started, we have kept records and photographs,” he said..

“If it were wildlife that is responsible, why are other farmers not losing sheep like this?

“You don’t have to be too smart to know, that a predator would kill a lamb.

“These lambs are still alive after their tongues are cut out.

We have to put them down or they would either bleed to death, or else they simply wouldn’t be able to eat and survive.”

His wife Bridget said: “It is someone who has got serious problems, there is something wrong with them.

“They must be getting some twisted kick out of this.”

Gerard is adamant that the attacks are not the result of an on-going feud.

“We have no quarrels with anyone, there is no reason in the world why someone would do this to us,” he said.

“And who would even think of doing such a thing to a young lamb.

“You cannot imagine what is inside that person’s head.”

During this spring’s lambing season, the McLaughlin’s say they have lost around 20 lambs to the attacks, and also two heavily pregnant sheep, which were carrying five lambs between them.

Despite efforts, which have included police surveillance with CCTV cameras, and private investigators, the family has never found any trace which would point towards the perpetrator.

Gerard says he is deeply frustrated by what he claims is the apparent lack of action by the police and government department - DARD.

“You see it often, these major operations against animal cruelty, and people are arrested,” he said.

“But this, what is happening here on this farm, is just the worst cruelty you can get.

“And yet it has been going on for over 20 years and is still going on.

“We have made hundreds of calls to police, the Department and to vets.

“How much more proof or evidence do they need?

“How many more animals will have to suffer and die like this, before these attacks are stopped?”

A spokesperson for the PSNI said: “Police have received numerous reports since 2000 of sheep mutilations at a farm in the Glenshane Road area. Police and a number of other specialist agencies have carried out full and thorough investigations and have continuously found no evidence of any offences having been committed. If anyone has a complaint about any police actions they should contact the office of the Police Ombudsman.”