Numbers 25:6-9

6Just then an Israelite man brought to his family a Midianite woman in the sight of Moses and the whole congregation of Israel while they were weeping at the entrance to the Tent of Meeting. 7On seeing this, Phinehas son of Eleazar, the son of Aaron the priest, got up from the assembly, took a spear in his hand, 8followed the Israelite into the tent, and drove the spear through both of them—through the Israelite and on through the belly of the woman.

So the plague against the Israelites was halted, 9but those who died in the plague numbered 24,000.