וְה֥וּא הִקְטִ֖יר בְּגֵ֣יא בֶן־הִנֹּ֑ם וַיַּבְעֵ֤ר אֶת־בָּנָיו֙ בָּאֵ֔שׁ כְּתֹֽעֲבוֹת֙ הַגּוֹיִ֔ם אֲשֶׁר֙ הֹרִ֣ישׁ יְהוָ֔ה מִפְּנֵ֖י בְּנֵ֥י יִשְׂרָאֵֽל׃
Moreover he offered in the valley of the son of Hinnom, and burnt his children in the fire, according to the abominations of the heathen, whom the LORD cast out before the children of Israel.
Read midrashic interpretation of II Chronicles 28:3: and classical rabbinic exegesis.