Mar 11, 2024 - History

Flashback: When nerve gas testing killed 7,000 sheep near Dugway in Utah

A newspaper headline states "Mystery Epidemic Kills 5,000 Sheep."

The Deseret News, Mar. 19, 1968. Image via Utah Digital Newspapers/University of Utah

"A sea of dead animals" was the description shared by witnesses who saw Utah's Skull Valley in March 1968 after thousands of sheep suddenly died — and changed America's weapons testing protocols.

  • This is Old News, our weekly autopsy of Utah's past.

Driving the news: About 6,400 sheep died in a single week 56 years ago, starting March 14. Another 600 were slaughtered because they could no longer move or eat.

  • Initially, the scientists who rushed to Utah suspected the herd was poisoned, possibly by plants they ate.

Yes, but: They also noticed the sheep were about 30 miles from the U.S. Army's Dugway Proving Grounds, where crews tested biological and chemical weapons.

Reality check: The Army was testing the VX nerve agent the day before the sheep dropped dead.

Under the rug: That detail emerged a week later, only after the Pentagon inadvertently released a "for official use only" report admitting to the tests.

  • Ranchers said they lost the chance to treat their sheep because of Dugway's false denials.

The intrigue: The Army insisted VX wasn't the culprit, noting the sheep didn't suffer some textbook symptoms of nerve gas poisoning.

The bottom line: The Army confirmed in a 1978 report — which wasn't publicly released until the Salt Lake Tribune obtained it 20 years later — that "incontrovertible" evidence showed VX was to blame.

The big picture: Most observers didn't need 30 years to reach that conclusion once the "Dugway sheep incident" became international news.

Previously in Old News:


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