SPRINGFIELD, Mo. (AP) — Investigators looking into the death of a Springfield zookeeper have concluded the man followed guidelines when he leaned partway into an elephant's cage before the animal lunged at him.

The Springfield News-Leader reports John Bradford was trying to get a female elephant at Dickerson Park Zoo to move into a restraint device Oct. 11.

The elephant lunged, knocking Bradford's head into a closed metal gate behind him. The animal crushed him with her head after his torso fell inside the cage.

Emergency responders believe he was killed instantly when his head hit the gate.

Bradford's death resulted in several procedural changes at the zoo.

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