'Wartime' in the Bible

"Furthermore, you're aware of what Zeruiah's son Joab did to me and to those two commanders of the armies of Israel, Ner's son Abner and Jether's son Amasa, whom he killed, and how he shed the blood of wartime during times of peace, staining the very belt he wears around his waist and the sandals he wears on his feet.

Therefore a disaster will come upon your people, and all of your fortresses will be ruined. As Shalman destroyed Beth-arbel in wartime, mothers were dashed to pieces along with their children.