And he brought out the grove from the house of the LORD, without Jerusalem, unto the brook Kidron, and burned it at the brook Kidron, and stamped it small to powder, and cast the powder thereof upon the graves of the children of the people. He brought out the grove - He brought out the idol Asherah. See at the end of 2 Kings 21:26 (note).
Upon the graves of the children of the people - I believe this; means the burial-place of the common people.