David has Uriah killed
David sent a letter to Joab telling him to put Uriah in a part of the battle where he would be killed. Joab did, and Uriah died.
Key passages
2 Sa 11:14–25

And it happened in the morning, David wrote a letter to Joab, and he sent it by the hand of Uriah. He had written in the letter, “Put Uriah in the front, in the face of the fiercest fighting, then draw back from behind him so that he may be struck down and die.” When Joab was besieging …