Judges 21:4

So it was, on the next morning, that the people rose early and built an altar there, and offered burnt offerings and peace offerings.

Surrounding context

21:3 and said, "O LORD God of Israel, why has this come to pass in Israel, that today there should be one tribe missing in Israel?"

21:4 So it was, on the next morning, that the people rose early and built an altar there, and offered burnt offerings and peace offerings.

21:5 The children of Israel said, "Who is there among all the tribes of Israel who did not come up with the assembly to the LORD?" For they had made a great oath concerning anyone who had not come up to the LORD at Mizpah, saying, "He shall surely be put to death."

Translation and sources