Tokyo stocks dived Thursday, with the Nikkei index hitting a roughly four-month intraday low, as the yen surged against the US dollar after the Bank of Japan left its monetary policy unchanged and the growing possibility that Britain could vote to leave the European Union weighed on sentiment. 
The 225-issue Nikkei Stock Average ended down 485.44 points, or 3.05%, from Wednesday at 15,434.14, its second-lowest level this year. The broader Topix index of all First Section issues on the Tokyo Stock Exchange finished 35.55 points, or 2.78%, lower at 1,241.56, according to Japan's (Kyodo) News Agency. 
Every industry category on the main section lost ground, led by real estate, nonferrous metals, and glass and ceramic products issues.