2 Samuel 3:26-28 Darby Translation (DARBY)
26 And 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.
27 And 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.
28 And afterwards David heard [it], and he said, I and my kingdom are guiltless before Jehovah for ever from the blood of Abner the son of Ner:
2 Samuel 3:26-28 New International Version (NIV)
26 Joab then left David and sent messengers after Abner, and they brought him back from the cistern at Sirah. But David did not know it. 27 Now when Abner returned to Hebron, Joab took him aside into an inner chamber, as if to speak with him privately. And there, to avenge the blood of his brother Asahel, Joab stabbed him in the stomach, and he died.
28 Later, when David heard about this, he said, “I and my kingdom are forever innocent before the Lord concerning the blood of Abner son of Ner.