What does Deuteronomy 3:6 mean?

We destroyed them completely, just like we did with King Sihon of Heshbon. We wiped out every man, woman, and child in those cities. Deuteronomy 3:6 - Modern Text Bible

(Israel carried out total destruction, following the same pattern as with Sihon. This was a harsh but common practice in ancient warfare, especially in the context of claiming the land.)