Números 21:24

24 Israel, however, put him to the sword and took over his land from the Arnon to the Jabbok, but only as far as the Ammonites, because their border was fortified.

24 But Israel overcame him, and took all his land from the Arnon to the Jabbok, as far as the country of the children of Ammon, for the country of the children of Ammon was strongly armed.