Investigators have opened more than 150 probes into a spate of killings and mutilations of horses across France, Agriculture Minister Julien Denormandie said on Wednesday.

“We have an unacceptable situation of absolutely sickening cruelty acts,” Denormandie told France Info radio.

“I hear the fear, the concerns, the disarray of horse owners,” he said, adding that a toll free number was being made available to horse owners from Wednesday morning.

Horses have been found with ears cut off, eyes gouged out and genitals mutilated. Police say they have no idea why; theories include a satanic rite, macabre trophy hunt or internet challenge. Most often, an ear — usually the right one — has been cut off, recalling the matador’s trophy in a bullring.

A 50-year-old jobless man arrested on Monday in eastern France as part of the investigation was released without charge, a police source said yesterday.

Up to 30 attacks have been reported in France, from the mountainous Jura region in the east to the Atlantic coast, many this summer, the agriculture minister said last week. One attack was registered in February, according to the news magazine Le Point. With each attack, the mystery only seems to grow.

With additional input from AP.