A two-year-old boy has been been mauled to death after falling into the African painted dog enclosure at Pittsburgh Zoo.
The boy was visiting the zoo with his 34-year-old mother, who had stood him up on the railings so he could get a better view of the dogs.
He slipped and fell 14ft into the enclosure, where he was pounced upon by a pack of 11 dogs.
Describing the incident as "horrific", Pittsburgh police major crimes Lt, Kevin Kraus, told the Post Gazette: "He lost his balance, fell down off the railing into the actual pit and he was immediately attacked by 11 dogs."
Zoo president Barbara Baker gave a press conference about the fatality, the first ever at Pittsburg, saying: "The keepers did everything they could do, they responded immediately and were able to get several of the dogs into the back-up building."
Vets tried to use tranquillisers darts to get the dogs away, but one particularly aggressive one would not the leave the child alone, and police were forced to shoot it dead.
Ms Baker has confirmed a medical examiner ruled that the boy was killed by the animals and not by the fall, telling NBC News: "What we understand from the medical examiner's report, the child did not die from the fall. The child was mauled by the dogs."
She said she could see the little boy's lifeless body lying on the hill in the exhibit below, adding: "There were three dogs: one at his head, one on the left side of his neck and another one down by his leg. ... A [zoo employee] got there and hopped over a fence with a rake and he was banging ... trying to distract the dogs but they wouldn't move."
African painted dogs are an endangered species that are as big as medium-sized domestic dogs, the zoo said.
In the wild, they are only found in Africa, especially in savannas and lightly wooded areas. They are also known as the African hunting dog or Cape hunting dog.
The dogs hunt in packs, usually living off impala, gazelle, springbok, and wildebeest calves, although they have been known to kill and eat zebras, warthogs, and even ostriches.
The dogs' technique of disembowelling their prey has earned them a ferocious reputation.
According to the Daily Telegraph, Ms Baker said the zoo will carry out an internal investigation, and decision has not yet been made about the future of the exhibit.
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