Interior Minister Joachim Brudzinski said on Twitter that the woman was detained Monday in the central city of Plock and would hear charges over the desecration of the icon of Mother of God of Czestochowa.
Last month, the woman, Elzbieta Podlesna, 51, placed posters with the altered icon on walls, garbage bins and mobile toilets near St. Dominik's church in Plock. In predominantly Catholic Poland, individuals can face up to two years in prison for hurting religious feelings.
Amnesty International has expressed concern that the human rights activist was detained shortly after a trip to Belgium and The Netherlands with the organization, and called the charges "spurious." Speaking on private TVN24 Tuesday, Podlesna denied her action was an attack on religion or on faith.
This story was earlier corrected to say Podlesna is not Amnesty International activist, but a human rights activist.