Tokyo stocks tumbled on Tuesday, with the Nikkei index ending 4.18 percent lower, hitting the lowest closing level since last October. The 225-issue Nikkei Stock Average dived 610.66 points, from Monday at 14,008.47, its lowest finish since Oct. 8. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 57.05 points, or 4.77 percent, at 1, 139.27. All of the 33 industry indexes fell, with the nonferrous metal, machinery and rubber sectors among major decliners. The turnover was 3636.4 billion yen (35.92 billion U.S. dollars).