The yen rapidly gained ground, reaching the ¥153-per-dollar level, while concerns grew over coordinated intervention by Japan and the United States and the Nikkei average fell by more than ¥1,000 at one point.
In the foreign exchange market, the yen rapidly strengthened, with reports that the dollar had reached the ¥153-per-dollar level.
Speculation emerged among market participants that preparations were under way for coordinated intervention by Japan and the United States, drawing attention to the rate check, a preparatory step for intervention.
Meanwhile, the Nikkei average fell by more than ¥1,000 at one point, as turmoil spread through the Japanese market.