Four new-born babies have been found dead - two of them in a basement freezer - at an apartment complex in the southern Austrian city of Graz.
A couple are suspected of having murdered the babies
Police are questioning a woman aged 32 - believed to be the mother - and her 38-year-old partner.
The first body was found on Monday - reportedly when a tenant went to get an ice cream for his daughter. Later another body was found in the freezer.
The third and fourth were in a paint bucket and under a pile of debris.
Sniffer dogs led police to the bucket, which had been filled with cement, and to the debris, which was in a garden shed.
The fourth body was found in a plastic bag on Friday at the residence, about 200 km (120 miles) south of Vienna.
Police are now trying to determine the cause of death in each case.
The woman, a bookkeeper, is reported to have admitted killing the babies in despair after giving birth.
The suspicious deaths are believed to have taken place over a period of three years.
Her partner is said to have denied knowing about her pregnancies. DNA tests have been ordered, to find out if he is the father.