Toshiba shares plunged again Wednesday as it warned of a $6.2 billion writedown in its US nuclear power business and announced a probe into possible wrongdoing by the unit's senior executives.
One of Japan's best-known firms, Toshiba shocked investors Tuesday when it failed to report its results for April-December as scheduled then said it needed more time to sort out the situation at troubled atomic division Westinghouse Electric.
Instead it issued a grim preliminary forecast forecast a net loss of 390 billion yen ($3.4 billion) in the fiscal year to March, dragged by a huge writedown topping 700 billion yen at Westinghouse.
The revelation prompted Toshiba chairman Shigenori Shiga to quit his post.
It also said lawyers and an independent auditing firm were sifting through details of an acquisition by Westinghouse, after a whistleblower complained executives exerted "inappropriate pressure" over accounting at the US-based company.
The firm's Tokyo-listed stock dropped more than 13 percent at one stage before paring losses to sit at 205.9 ($1.80) by the lunch break, down 10.4 percent and extending Tuesday's eight percent selloff.
The crisis comes less than two years after the conglomerate, which makes everything from trains to memory chips, suffered an embarrassing profit-padding scandal that involved bosses pressuring subordinates to cover up weak earnings.
The company's stock has lost 60 percent since that crisis came to light in April 2015.
"There is no room for optimism," said Toshihiko Matsuno, chief strategist at SMBC Friend Securities.
"The share price is still higher than the low at the time of the accounting scandal when investors were pricing in the possibility of its shares being taken off the exchange," he told AFP, adding that the firm was likely working to avoid an embarrassing delisting.
"Its corporate governance has been called into question and I cannot rule out the possibility that investors are pricing that scenario in" again.
On Tuesday, Toshiba warned that any improper accounting at its US nuclear power unit could affect its latest earnings.
"The questions surrounding Toshiba are so numerous, where do you even begin," Masahiko Ishino, an analyst at Tokai Tokyo Securities, told Bloomberg News.
"Investors want to know what will happen to its nuclear and chip businesses, whether elevator operations and some of Toshiba's listed subsidiaries will be sold off. There is also the question of why the nuclear writedown happened in the first place.
The industrial giant once touted its overseas nuclear business as a future growth driver, filling a hole left after the 2011 Fukushima crisis slammed the brakes on new atomic projects in Japan.
But it turned out to be a bad bet and on Tuesday it confirmed speculation it would dramatically reduce its nuclear ambitions overseas.
It said it would stop building new atomic power plants, but would continue making related equipment.
And company officials have approached South Korean utility Korea Electric Power Corp about buying part of its stake in British nuclear joint venture NuGeneration.
The atomic strategy U-turn comes as Toshiba undergoes a major restructuring following its 2015 accounting scandal.
It has sold its medical devices unit to camera and copier maker Canon and most of its appliance business to China's Midea Group while it is also moving to spin off its prized memory chip unit.