1 Kings 16:16

and the troops who were encamped heard it said , Zimri has conspired , and he has killed the king . Therefore all Israel made Omri , the commander of the army , king over Israel that day in the camp .

When the Israelites in the camp heard that Zimri had plotted against the king and murdered him, they proclaimed Omri, the commander of the army, king over Israel that very day there in the camp.

And the people that were encamped heard say, Zimri hath conspired, and hath also slain the king : wherefore all Israel made Omri, the captain of the host, king over Israel that day in the camp.