Num 21:22-24

22“Let me pass through your land; we will not turn aside into field or vineyard; we will not drink the water of any well; we will go by the King's Highway until we have passed through your territory.”23But Sihon would not allow Israel to pass through his territory. Sihon gathered all his people together, and went out against Israel to the wilderness; he came to Jahaz, and fought against Israel.24Israel put him to the sword, and took possession of his land from the Arnon to the Jabbok, as far as to the Ammonites; for the boundary of the Ammonites was strong.