2 Samuel 3:22-27

22And behold, the servants of David and Joab came from an expedition, and brought in a great spoil with them; but Abner was no longer with David in Hebron, for he had sent him away, and he had gone in peace.

23And Joab and all the host that was with him came; and they told Joab, saying, Abner the son of Ner came to the king, and he has sent him away; and he is gone in peace.

24Then Joab came to the king, and said, What hast thou done? behold, Abner came to thee; why is it [that] thou hast sent him away, and he is gone?

25Thou knowest Abner the son of Ner, that he came to deceive thee, to know thy going out and thy coming in, and to know all that thou doest.

26And when Joab was come out from David, he sent messengers after Abner, who brought him again from the well of Sirah; but David did not know it.

27And when Abner was returned to Hebron, Joab took him aside in the gate to speak with him secretly, and smote him there in the belly, that he died, for the blood of Asahel his brother.