2 Samuel 20:10

But Amasa took no heed to the sword that was in Joab's hand, namely, in his left, with which he had just picked it up; so he, Joab, smote him therewith in the fifth rib, in the abdomen, and shed out his bowels to the ground, and struck him not again, for there was no need for repeating the blow; and he died. It was a cold-blooded murder, an act of malice, the product of jealousy and the desire for revenge. So Joab and Abishai, after the murder of Amasa, pursued after Sheba, the son of Bichri.