Experts on a mission to crack America's 'longest-running murder mystery' have unearthed new clues in a puzzle that has haunted ranchers since the 1970s.

From Kansas to Oregon, there have been eerie incidents of cattle found slain, their reproductive organs surgically removed, yet not a drop of blood left behind at the scenes.

These bizarre occurrences sparked fears of extraterrestrial beings with an odd fascination for bovine anatomy. However, an ex-rancher from Oregon posits that these bovine deaths are the work of a "sophisticated network of humans."

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