2 Kings 16:3-4

3Instead he walked in the way of the [idolatrous] kings of Israel, and even made his son pass through the fire [as a human sacrifice], in accordance with the repulsive [and idolatrous] practices of the [pagan] nations whom the Lord drove out before the Israelites.

4He also sacrificed and burned incense on the high places and on the hills and under every green tree.