2 Samuel 3:24-27

24Joab rushed to the king and demanded, “What have you done? What do you mean by letting Abner get away?

25You know perfectly well that he came to spy on you and find out everything you’re doing!”

26Joab then left David and sent messengers to catch up with Abner, asking him to return. They found him at the well of Sirah and brought him back, though David knew nothing about it.

27When Abner arrived back at Hebron, Joab took him aside at the gateway as if to speak with him privately. But then he stabbed Abner in the stomach and killed him in revenge for killing his brother Asahel.