2 Chronicles 33:23 (KJV)

Amon was two and twenty years old when he began to reign, and reigned two years in Jerusalem.

But he did that which was evil in the sight of the Lord, as did Manasseh his father: for Amon sacrificed unto all the carved images which Manasseh his father had made, and served them;

And humbled not himself before the Lord, as Manasseh his father had humbled himself; but Amon trespassed more and more.

And his servants conspired against him, and slew him in his own house.

But the people of the land slew all them that had conspired against king Amon; and the people of the land made Josiah his son king in his stead.