Boy's zoo death 'a horrible tragedy'

The president of a zoo where a two-year-old boy fell into an enclosure and was mauled to death by African wild dogs said it had met or exceeded safety standards, proving that no exhibit was "fail-proof".

Nearby staff responded "within seconds" on Sunday but quickly determined the dog attack was fatal and did not send handlers into the enclosure to intervene, Pittsburgh Zoo and PPG Aquarium's Barbara Baker said.