Then Abner said to Joab, "Let's have some of the young men get up and fight hand to hand in front of us." "All right, let them do it," Joab said.
So they stood up and were counted off--twelve men for Benjamin and Ish-Bosheth son of Saul, and twelve for David.
Then each man grabbed his opponent by the head and thrust his dagger1 into his opponent's side, and they fell down together. So that place in Gibeon was called Helkath Hazzurim.
References for 2 Samuel 2:16
The battle that day was very fierce, and Abner and the men of Israel were defeated2 by David's men.3
References for 2 Samuel 2:17