Numbers 31:5-8

5So twelve thousand men armed for battle, a thousand from each tribe, were supplied from the clans of Israel.

6Moses sent them into battle, a thousand from each tribe, along with Phinehas son of Eleazar, the priest, who took with him articles from the sanctuary and the trumpets for signaling. 7They fought against Midian, as the LORD commanded Moses, and killed every man. 8Among their victims were Evi, Rekem, Zur, Hur and Reba—the five kings of Midian. They also killed Balaam son of Beor with the sword.