Numbers 25:6-8, 14-15

Then an Israelite man brought into the camp a Midianite woman right before the eyes of Moses and the whole assembly of Israel while they were weeping at the entrance to the tent of meeting. When Phinehas son of Eleazar, the son of Aaron, the priest, saw this, he left the assembly, took a spear in his hand and followed the Israelite into the tent. He drove the spear into both of them, right through the Israelite man and into the woman’s stomach. Then the plague against the Israelites was stopped

The name of the Israelite who was killed with the Midianite woman was Zimri son of Salu, the leader of a Simeonite family. And the name of the Midianite woman who was put to death was Kozbi daughter of Zur, a tribal chief of a Midianite family.