The 2-year-old fell off an observation deck that sits 14 feet above an enclosure for the African painted dogs. There were 11 dogs in the enclosure but the zoo says a painted dog keeper was able to get seven dogs off exhibit upon first notification of the accident.
According to the zoo, darts were also shot into the exhibit in an attempt to scare off the animals, but the dogs were in pack mentality and did not respond. Keepers along with the Pittsburgh police also tried to lure some of the dogs away. One dog that was reportedly being aggressive was shot and killed by an officer.
A zoo official said it's not clear whether the child died as a result of the attack or the fall.
The dogs are about as big as medium-sized domestic dogs, 2 to 2 1/2 feet high and 37 to 80 pounds. They are considered endangered.
The accident is being investigated by both the zoo and the Pittsburgh Police Department. Meantime, the Pittsburgh Zoo & PPG Aquarium will be closed until further notice.
In May, some of the African painted dogs escaped into a part of the exhibit that's usually closed. The zoo was on lockdown for about an hour as a precaution.
The Associated Press contributed to this report.