A 53-year-old woman was arrested in Osaka on Tuesday after she confessed to dumping in buckets the dead bodies of four babies she had given birth to over a five-year period and covering them with concrete.

Mayumi Saito turned herself in Monday and the police found four concrete-filled buckets in a closet in her condominium in Neyagawa, Osaka Prefecture.

Imaging analysis has confirmed that all of the buckets contain human bones, apparently those of babies.

Investigative sources believe that the four babies were born to Saito and a single partner. They will conduct autopsies while looking into the circumstances of the babies' deaths.

The statute of limitations for abandoning a body is three years, but Saito was arrested for taking the body of one of the babies from a different location to her condominium, which she moved into in 2015, the police said.

She told the police she dumped the dead babies in buckets between 1992 and 1997, saying she did not have money to raise them.

She also said she felt guilty about abandoning the infants over the years, but had no one she could talk to about it, according to the police.