Thousands of Coho salmon died at a fish hatchery in Beulah, Missouri - and officials say that vandals are to blame.
Staff at the Platte River State Fish Hatchery arrived for work to find around 5,700 dead fish in the maturation pond.
Further investigation revealed some very large travel hooks and heavy line. Fish production manager Edward Eisch said: "We believe they were trying to snag some fish out the pond…it appears the fish were forcibly crowded into a small area which blocked water flow through the screens and created conditions in which the dissolved oxygen concentrations became lethal.
"A lot of effort went into raising those fish and they were sacrificed to stupidity."
Security at the facility will be stepped up as a result, and an investigation is under way to find those responsible.
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