31 The LORD said to me, "See, I have begun to deliver Sihon and his country over to you. Now begin to conquer and possess his land."
32 When Sihon and all his army came out to meet us in battle at Jahaz, 33 the LORD our God delivered him over to us and we struck him down, together with his sons and his whole army. 34 At that time we took all his towns and completely destroyed [c] them—men, women and children. We left no survivors. 35 But the livestock and the plunder from the towns we had captured we carried off for ourselves. 36 From Aroer on the rim of the Arnon Gorge, and from the town in the gorge, even as far as Gilead, not one town was too strong for us. The LORD our God gave us all of them. (Deut 2)
3 So the LORD our God also gave into our hands Og king of Bashan and all his army. We struck them down, leaving no survivors. 4 At that time we took all his cities. There was not one of the sixty cities that we did not take from them—the whole region of Argob, Og's kingdom in Bashan. 5 All these cities were fortified with high walls and with gates and bars, and there were also a great many unwalled villages. 6 We completely destroyed [a] them, as we had done with Sihon king of Heshbon, destroying every city—men, women and children. 7 But all the livestock and the plunder from their cities we carried off for ourselves. (Deut 3)
20 When the trumpets sounded, the people shouted, and at the sound of the trumpet, when the people gave a loud shout, the wall collapsed; so every man charged straight in, and they took the city. 21 They devoted the city to the LORD and destroyed with the sword every living thing in it—men and women, young and old, cattle, sheep and donkeys. (Joshua 6)
11 As soon as he began to reign and was seated on the throne, he killed off Baasha's whole family. He did not spare a single male, whether relative or friend. 12 So Zimri destroyed the whole family of Baasha, in accordance with the word of the LORD spoken against Baasha through the prophet Jehu- 13 because of all the sins Baasha and his son Elah had committed and had caused Israel to commit, so that they provoked the LORD, the God of Israel, to anger by their worthless idols. (I Kings 16)
I think the Bible (especially the Old Testament) is as bloody and full of vengeance as the Koran.