CHICAGO (CBS) — Detectives are investigating after a badly decomposed body was found Wednesday morning in a semi-trailer in the Back of the Yards neighborhood on the South Side.

Officers responded about 10 a.m. after the body, thought to be an adult, was discovered in the 2000 block of West 43rd Street, according to Chicago Police.

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The person’s identity has not been released, the Cook County medical examiner’s office said.

A police source said the skeletal remains were found by a truck yard employee, who then called 911. The person’s gender and age could not be determined.

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The person was found underneath blankets and no foul play was suspected, the source said.

No one was in custody Thursday morning as Area Central detectives were conducting a death investigation.

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