LXX Num 21:23

καὶ οὐκ ἔδωκεν Σηὼν τῷ Ἰσραὴλ παρελθεῖν διὰ τῶν ὁρίων αὐτοῦ· καὶ συνήγαγεν Σηὼν πάντα τὸν λαὸν αὐτοῦ, καὶ ἐξῆλθεν παρατάξασθαι Ἰσραὴλ εἰς τὴν ἔρημον· καὶ ἦλθεν εἰς Εἴσσα, καὶ παρετάξατο τῷ Ἰσραήλ.

But Sihon would not let Israel pass through his territory. Instead, he gathered his whole army and went out to confront Israel in the wilderness. When he came to Jahaz, he fought against Israel.