A Polish woman has been arrested on suspicion of killing at least five of her newborn babies, a prosecutor said Friday.

The suspect, identified only as 41-year-old Beata Z., has been questioned and will be held for at least three months during an investigation, said Maria Kudyba, a prosecutor in Lomza in northeastern Poland.

Kudyba said the widowed woman gave birth to eight babies between 1998 and 2012, but only two remain alive.

Four bodies of babies have been found on the woman's farm in Hipolitowo village. Investigators are searching for a fifth body and trying to determine the fate of the sixth baby.

Autopsies will be carried out to confirm that Beata Z. is their mother, and she will undergo psychiatric examination.

Social workers alerted police this summer when they saw no baby born after Beata Z. appeared to have been pregnant.

Investigators refused to speculate about possible motives in the case, which has been widely covered by the Polish media.

Poland, which is predominantly Catholic, has a strict anti-abortion law that allows the termination of a pregnancy only if it threatens the life of the mother, the fetus is irreparably damaged, or the pregnancy resulted from a crime.