A small boy has died after falling into an enclosure of African wild dogs at a zoo in the US city of Pittsburgh.
The child, said to have been aged about three, had been on an outing with his mother when he fell over a railing and off a mesh barrier into the exhibit.
Zoo keepers called off most of the 11 dogs, but one refused to move away from the boy and was shot dead.
The zoo was closed after the incident, and an investigation by the police and the zoo is under way.
"It is with great sadness and very, very heavy hearts that we report today that a small child was killed by our African painted dog pack this morning," head of the zoo, Barbara Baker, told a news conference.
She said it was clear the dogs had attacked the boy, but that "whether he died of the attack or the fall has yet to be determined".
No decision had been made about the future of the enclosure, she said.
African painted dogs, also known as African wild dogs, are an endangered species. They are the size of medium domestic dogs and hunt in packs.