TOKYO, May 30 (Xinhua) -- Tokyo stocks closed lower Wednesday, with the benchmark Nikkei stock index hitting a month-and-a-half low on investor concerns over political turbulence in Italy, with Wall Street's retreat overnight also weighing on the market.

The 225-issue Nikkei Stock Average dropped 339.91 points, or 1.52 percent, from Tuesday to close the day at 22,018.52.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, lost 25.72 points, or 1.46 percent, to finish at 1,736.13.

Nonferrous metal, insurance, and glass and ceramic product-oriented issues comprised those that declined the most by the close of play.