PHILADELPHIA (CBS) — Philadelphia Police are investigating a disturbing discovery on a North Philadelphia street Monday night.

People walking along the 3100 block of W. Clearfield Street came across an infant- or child-sized casket lying on the sidewalk just after 9 p.m.

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“I was pretty shocked,” said Chris James. “It looked like something straight out of ‘Thriller.'”

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Officers arrived and opened the casket to find a bag of organs inside, but no body.

“According to the medical examiner, [they] were in fact human organs. They believed they belonged to an infant or a child,” said Chief Inspector Scott Small. “What’s unusual is other than the bag of organs there was no body.”

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Small described the casket as “fresh” and recently pried open. Investigators are looking into whether someone stole it from an area funeral home or if it was dug up from a cemetery, including Mt. Vernon directly across the street from where the casket was found.

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“There have been cases where people take remains or human bodies for whatever unusual reason they decide,” Small said, “but we’re going to look into that.”

The Office of the Medical Examiner now has the casket and the organs for further investigation.

Police plan to have cadaver dogs search Mt. Vernon and Laurel Hill cemeteries nearby for freshly dug up graves.

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