Investigators searching a property in Philadelphia's Olney neighborhood have determined that bones found last week were animal bones, according to sources.

Sources also said that adipocere, a wax-like substance that can form during decomposition, was discovered during the ongoing excavation of the property.

"Adipocere is a tissue which can be used to identify a person," said Fabio Oldoni, an associate professor, program director and forensic geneticist at Arcadia University.