The baby was discovered in the afternoon of Sept. 23 at the intersection of Patterson Avenue and Snowden Road, Upper Darby police said on Facebook Wednesday.
A passerby reportedly found the infant's body in a trash bag on the sidewalk around 4 p.m, several news reports say.
Authorities did not disclose how long the infant was outside nor the sex of the baby.
They are asking anyone with information about the identity of the infant or anyone associated with the baby to contact Detective Sergeant Daniel Oliveri at 267-566-1824 or doliveri@udpd.org.
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