French authorities have been left mystified over a spate of gruesome horse mutilations that have gripped the country in recent weeks. 

At least 30 attacks have been logged this year, with the earliest one dating back to February and the most recent one taking place this Thursday, French media reported. 

The attackers, armed with knives and an apparent knowledge of horses, have been sneaking into pastures and stables at night and dismembering the animals. 

"There is clearly a professionalism, people acting with a certain level of technique," Agriculture Minister Julien Denormandie said on Friday, vowing to bring the perpetrator or perpetrators to justice. 

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Gruesome attacks 

In most cases, the attackers cut off one of the horses' ears — similar to a matador's trophy in the bullring. 

"Ears are cut off, eyes removed, an animal is emptied of its blood ...," Denormandie said during a visit to a stable in central France where a horse was recently attacked.  

In a case last week, a mare in southeastern France was found disemboweled next to a pony with a ripped ear. Sometimes the perpetrators take parts of bone or parts of the animal's nose, targeting donkeys and ponies as well as horses. 

"It is cruel savagery of a kind we have rarely seen before," the president of the French Equestrian Federation, Serge Lecomte, told news agency AFP. 

"Is it a cult? Cruelty towards animals is the precursor to cruelty towards humans," he added. 

Mystery over perpetrators 

Police are still at a loss as to who is behind the disturbing attacks. Some of the current theories include that it could be a ritual of an unknown cult, or possibly a disturbing "challenge" circulating on social media, or the result of copycat actors. 

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Some perpetrators were spotted for the first time last Monday when the head of a horse riding center in the Burgundy region came across two attackers. 

The head of the center, Nicolas Demajean, said his squealing pigs alerted him to the danger. When he headed out to investigate, he encountered two attackers. Demajean was injured by one assailant with a pruning knife while the second attacker slashed at the sides of two ponies. 

The ponies are recovering from the attack but are "traumatized," he told regional TV station France 3.  

"I used to have confidence putting my horses out to pasture. Today, I have fear in my gut,'' he told the station.  

rs/dj (AP, AFP)