Workers clearing an apparently vacated apartment in Hokkaido found the body of a dead newborn among the former residents' belongings, police said Thursday.

The workers notified police in Sapporo late Wednesday afternoon after they discovered the corpse wrapped in a black plastic garbage bag and stuffed in a portable ice chest, police official Takaaki Ando said.

The landlord had hired the workers to clear the apartment after several months had passed without any contact from the residents, Ando said.

Police are awaiting autopsy results to determine how the infant died, including whether it was stillborn, he said. The body, which appears to be female, was already showing signs of decomposition, he added.

Police are looking for the former residents to question them, he said, without providing any further identification.