Spanish police were on Tuesday investigating the decapitation of a European bison and the disappearance of three others from a nature reserve which was set to start a breeding programme for the species.
The headless body of Sauron, the 660-kilo (1,455-pound) dominant male of a small herd, was found Friday at the private Valdeserillas reserve in the eastern region of Valencia, reserve spokesman Rodolfo Navarro told AFP.
The animal may have been decapitated by hunters that wanted its head as "a trophy", he said.
Sauron appeared to have been decapitated with an axe, the central government's representative in Valencia said.
Three others from the eight-strong herd are missing and could be sick or frightened, Navarro said.
Staff were searching the 330-hectare (815-acre) reserve for the missing animals including in areas that can only be reached by foot, he added.
The rest of the herd were sick earlier this month, possibly due to poisoning, Navarro said.
The owners of the reserve plan to introduce female bison to the site later this year to allow the herd to reproduce.
The European bison, the continent's largest wild land mammal, once roamed across most of the continent but it was severely hunted until it finally became extinct in the wild in 1927, according to the World Wildlife Fund.
The animal has been reintroduced into the wild across Europe over the past few decades and the species' global population now stands at around 5,500, according to the environmental organisation.
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