PITTSBURGH (November 6, 2012)--The medical examiner's office says a 2-year-old boy who died in the Pittsburgh zoo's African wild dog exhibit bled to death the animals mauled him.

Police and officials at the Pittsburgh Zoo and PPG Aquarium are investigating the death of Maddox Derkosh, which happened Sunday after he fell from a wooden railing overlooking the painted dogs exhibit.

The Whitehall boy's funeral is Friday and his parents are asking friends, relatives and other mourners to donate toy construction trucks in the boy's name, which will be given to a Christmas children's charity.

The Allegheny County Medical Examiner has yet to rule on whether the boy’s death was an accident until police determine whether anyone will be charged.

The boy's family has not commented.