sheep incident sheep incident known sheep kill sheep kill connected united_states_army chemical biological warfare programs proving ground utah thousand sheep killed near base popular explanation blamed army testing chemical weapons incident alternative explanations offered report commissioned officer public called documented admission army nerve agent killed sheep background founding activity proving ground closely guarded secret activities included aerial nerve agent testing according reports producing small quantities late years united_states renounced biological weapons chemical tests time period sheep incident total nerve agent dispersed open air tests tests weapons mass destruction including open air tests biological weapons dirty bomb tests nuclear material open air conditions simulate dispersal fallout case nuclear incident days preceding sheep incident united_states_army proving ground conducted separate operations involving nerve agents operations occurred march involved test firing chemical artillery shell burning gallons nerve agent open air pit jet aircraft sprayed nerve agent target area west event usually connected skull valley sheep kill incident log proving ground indicated sheep incident began phone march director ecological contract chief ecology branch report sheep dead area initial report incident came manager livestock company sheep grazing area proving ground total sheep deaths reported days result incident attempt count dead sheep compiled total possible causes previously obtained documents said demonstration occurred day sheep deaths march phantom strike aircraft flew test mission proving ground chemical containing completely emptied test gained altitude bombing run trail aircraft drifted north proving ground settled huge flock sheep explanation aftermath incident chemical biological agent escaped proving ground evidence support assertion united_states_army admitted conducting open air tests nerve agent days preceding sheep kill army spray test causing aircraft continue climbed higher altitudes reported small found tissue dead sheep information contradicted initial assumptions contradiction nerve agent exposure cause came symptoms sheep following incident sheep alive sat ground sheep refused eat exhibited normal breathing patterns showed signs internal regular breathing internal inconsistent nerve agent exposure animals type including cows horses dogs rabbits birds appeared suffered ill effects hard explain fact caused sheep deaths aftermath incident affected army military policy year international incident contributed president richard_nixon decision ban open air chemical weapon testing sheep incident events helped contribute rise public sentiment vietnam war ultimately disbanded result following incident army state federal agencies compiled reports later characterized studies report remained classified unreleased public nearly years incident called documented admission army killed sheep reporting content report public time report described evidence nerve agent cause sheep kill report compiled researchers maryland stated found snow grass samples recovered area weeks sheep incident report concluded quantity originally present sufficient account death sheep report surfaced army maintained accept responsibility incident admit late year report went public officials stated reason report published wasn particularly revealing news reported june owned sheep killed outside working incident members family developed nervous system illnesses similar reported people exposed low levels lab experiments probe showed medical tests army claim humans affected considered inconclusive shown signs low level exposure
Dugway sheep incident