The Nikkei average tumbled 3.07 per cent today to book its biggest one-day loss in a year as exporters fell on persistent concern about a slowdown in the key market of the United States.
Nippon Steel and other steel firms lost ground as sharp declines in the market forced retail investors who were engaged in margin trading to sell shares to cut losses, helping the TOPIX to extend losses.
The Nikkei broke below 15,000 for the first time this year and fell 462.98 points to end at 14,633.03, the lowest close since November last year. So far this year, the benchmark has shed more than 9 per cent.
Exporters lost ground, with Honda giving up 3.6 per cent to 6,930 yen. Technology shares, many of which depend on sales in overseas markets, also met heavy selling.
Tokyo saw its busiest day of stock trading in nearly five months, as 2.65 billion shares changed hands on the exchange's first section.
Declining shares overwhelmed advancers by a ratio of 41 to 1.