MILAN (AP) — A brass plaque memorializing a Nazi Holocaust victim in Rome has been defaced with a sticker reading in German, "Murderers always return to the crime scene."

Corriere della Sera on Thursday reported the threatening message on the so-called "stumbling stone," which was first noted by the association "Art in Memorial" that maintains the stones.

Rome's chief rabbi, Riccardo Di Segni, called the message "spine-chilling" and said more than vandalism it was "a provocation." He noted that the location of the stone was on Via della Reginella, a key location for the deportation of Jews from Rome.

Twenty of the memorial brass cobblestones were stolen last December. They are part of a 1992 project by a German artist to mark the former residences of Holocaust victims.