An employee sorting through recycling materials found the body just before noon at the MRF recycling plant on the 17000 block of Abbey Lane, KABC-TV, Los Angeles, reported.
"The sheriff's department is asking that the public, anyone who has information of a female may have recently given birth and who does not have their baby in their custody, that they would please call sheriff's homicide," Jodi Miller with the San Bernardino County Sheriff's Department said.
It wasn't clear if the baby was stillborn or the victim of a homicide, and an autopsy was pending, detectives said.
Anyone with information was asked to call (909) 387-3589.
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