וְעַצְמוֹת֙ כֹּֽהֲנִ֔ים שָׂרַ֖ף עַל־מזבחותים [מִזְבְּחוֹתָ֑ם] וַיְטַהֵ֥ר אֶת־יְהוּדָ֖ה וְאֶת־יְרוּשָׁלִָֽם׃
And he burnt the bones of the priests upon their altars, and purged Judah and Jerusalem.
Read midrashic interpretation of II Chronicles 34:5: and classical rabbinic exegesis.