WASHINGTON (AP) -- Officials with the Smithsonian's National Zoo say a zebra attack that seriously injured a veteran zookeeper was the result of human error.
The zoo released a summary of its safety investigation into the incident on Friday. It says the 900-pound zebra got through an unlocked stall gate into a holding yard, where it kicked and bit zookeeper Wayne Millner.
A statement from the zoo says the zebra "should have been contained in his primary stall."
Millner was hospitalized, and the zoo has said he has no memory of the incident.
The report comes two days after the zoo released reports that detailed serious problems with its animal care. Several animals have died recently, and zoo director Dennis Kelly has said his staff is stretched thin because of budget cuts.
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