Mourners laid flowers and lit candles Saturday at an apartment complex in southern Austria where police found the bodies of four slain infants — two stuffed in a basement freezer and two sealed in concrete-filled buckets.

Authorities questioned the babies' 32-year-old mother in hopes of piecing together the chain of events that led to the deaths. Police investigated whether the woman and her longtime male companion had recently lived anywhere else besides the building on the outskirts of Graz, 120 miles south of Vienna.

The woman, whose name was not released under Austrian privacy laws, has confessed to killing the children out of despair for her financial troubles and fears of driving away her longtime partner, investigators told the Austria Press Agency.

Although officials initially considered the possibility that the infants may have been stillborn, evidence at the scene also pointed to slayings, police said in a statement.

Police have said they believed the bodies may have been placed in the freezer as long as three years ago. She had lived in the building with her partner for the past eight years, authorities said.

DNA tests are under way to determine whether the partner — a 38-year-old carpenter — is the father of the children, police said Saturday. Her partner said he was unaware of her pregnancies and that he played no role in either the slayings or the hiding of the bodies.

Autopsies were expected to be complete by Monday.

The couple appeared before a judge late Friday and were interrogated, police said. The mother has not been entirely coherent during questioning, Lt. Col. Werner Jud said.

"The woman has not been able to say in what order the babies were born," Jud was quoted by APA as saying.

Authorities have fanned out to question neighbors and others who might have known the couple. People who lived near their home in Graz described the woman — a bookkeeper who worked at a gas station — as a hard worker and a kind person who kept a lovely yard.

"She was very thin — you would have noticed if she had been pregnant," said a distraught middle-aged neighbor who gave her name only as Renate.