(AP) -- BRECKENRIDGE HILLS, Mo. (AP) -- A healthy baby boy abandoned in a St. Louis County apartment building has been placed in state custody while police try to learn his identity and find his parents.

The St. Louis Post-Dispatch reports the infant appears to be 4 to 6 months old and was found fully dressed, with a full bottle, in what police described as an expensive car seat.

Someone called Breckenridge Hills police after finding the baby around 5 a.m. Friday in a hallway at the Hickory Trace apartment complex.

Residents of the building told police they had never seen the infant before. Police were contacting people throughout the 10-building complex hoping for information.

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