In the twenty-seventh year of Judah's King Asa, Zimri became king for seven days in Tirzah. Now the troops were encamped against Gibbethon of the Philistines.
References for 1 Kings 16:15
When the encamped troops heard that Zimri had not only conspired but had also struck down the king, then all Israel made Omri, the army commander, king over Israel that very day in the camp.
Omri along with all Israel marched up from Gibbethon and besieged Tirzah.
When Zimri saw that the city was captured, he entered the citadel of the royal palace and burned down the royal palace over himself. He died
because of his sin he committed by doing what was evil in the Lord's sight and by following the example of Jeroboam and the sin he caused Israel to commit.
The rest of the events of Zimri's [reign], along with the conspiracy that he instigated, are written about in the Historical Record of Israel's Kings.