In this undated photo provided by Silvies Valley Ranch, a Hereford bull lies dead in Burns, Ore., one of five apparently healthy bulls that were found dead and with sex organs and tongues removed. Authorities suspect the bizarre deaths and mutilations were human caused, but have no leads. The deaths of the bulls recall mutilations of livestock across the West and Midwest in the 1970s that struck fear in rural areas, and caused people to carry guns. (Silvies Valley Ranch via AP)
A Hereford bull lies dead in Burns, Oregon, with its sex organs and tongue removed (Picture: AP)

Five bulls have been found killed with their genitals mutilated and their blood drained.

The horrifying discovery has prompted locals near the scene in Oregon, USA, to speculate the deaths could be an occult ritual or even an alien invasion.

Experts have dismissed natural causes or predators for the deaths of the cattle at Silvies Valley Ranch.

Cowboys made the successive gruesome discoveries of the purebred bulls.

The first was found with no sex organs, tongue or blood in a ravine in the Oregon countryside, near the town of Burns.

Four more were later found over the summer in similar conditions.

Vice President of the ranch, Colby Marshall, said: ‘To lose a completely healthy animal would be an oddity.

‘To lose five young, very healthy, in great shape, perfect bulls that are all basically the same age…that is so outside the bounds of normal activity.’

- In this Sept. 21, 2017 photo provided by Silvies Valley Ranch, Colby Marshall, vice president of Silvies Valley Ranch poses for a picture in Burns, Ore. Silvies Valley Ranch owns five bulls that were found dead with sex organs and tongues removed. The deaths of the bulls recall mutilations of livestock across the West and Midwest in the 1970s that struck fear in rural areas, and caused people to carry guns. Marshall believes a cult is behind the bull deaths. (David Zaitz/Silvies Valley Ranch via AP)
Colby Marshall, vice president of Silvies Valley Ranch, says he thinks it is a cult killing the cows (Picture: AP)

The case eerily echoes previous mutilations of livestock across the West and Midwest of the USA in the 1970s.

In the 1980s a few cows were found dead and mutilated in Oregon and last year there were a few cases in Arizona.

The FBI became involved in those cases and has so far refused to confirm or deny that it is looking into the latest cattle deaths.

There were no tracks around the bodies or other clues as to how they died.

This has led police and managers at the ranch to speculate they were executed by someone rather than something.

Harney County Sheriff’s Deputy Dan Jenkins is working on the case and said he has had dozens of calls offering tips and suggestions.

He said one suggestion was to look for a crater underneath the carcass, which would be evidence it had been dropped from a great height.

Mr Jenkins said: ‘A lot of people lean toward the aliens.

‘One caller told us to look for basically a depression under the carcass.

‘Because he said that when the alien ships will kinda beam the cow up and do whatever they are going to do with it, then they just drop them from a great height.’

The Harney County Sheriff’s Office has ruled out bears, wolves, cougars or poisonous plants.

Nor were the animals shot.

Officials at the ranch have put out a $25,000 (£20,400) reward for any information.

Mr Marshall speculated that they were darted with a tranquiliser to knock them out.

He said some people would act as lookouts while others bled the animals out by inserting a needle into a tongue and a main artery.

The sex organs were then removed with a scalpel after their death.

Mr Marshall added: ‘We think that this crime is being perpetuated by some sort of a cult.’

He said he doubted it was a malicious attack on the ranch, a 140,000 acre estate which employs 75 local people.

Instead, he thinks the cattle were killed by people wanting to get the genitals for some reason.

Mr Jenkins at the Sheriff’s Office agreed, adding: ‘Personally, I would lean more toward the occult, where people for whatever reason – whether it’s a phase of the moon or whatever rituals they’re going to do with their beliefs – are coming to different areas and doing that.’

Silvies Valley Ranch was bought in 2006 by a wealthy vet and as well as being a working ranch is also an elite resort with four golf courses, shooting ranges and cabins that go for up to $849 (£690) a night.

The bulls were worth $6,000 (£4,900) each but their future calves would have a combined worth of several hundreds of thousands.