Gardaí say a skull and bones uncovered at a recycling plant in County Wicklow were "medical specimens" used for teaching.
The human remains were found at a plant in Bray yesterday.
Following examination by forensic experts, investigators said the bones were donated to science for the purpose of training medical professionals.
They have since been "returned to their rightful owner."
The Garda investigation concluded that no offence was committed.
It is believed the remains were found at the same recycling plant where the body of a baby girl was found in 2016.
A post-mortem later found that the recently born baby was not deliberately harmed.