Shares tumble more than 10% over huge loss warning
The stock plunged 12.23 percent to 201.7 yen in the first several minutes of trading.
Toshiba on Tuesday issued a grim preliminary earnings forecast, which prompted its chairman to resign as it hinted at a fresh accounting scandal.
Toshiba warned it was on track to report a net loss of 390 billion yen ($3.4 billion) in the current fiscal year to March, as it faced a huge writedown topping 700 billion yen at Westinghouse.
The Japanese industrial giant said that lawyers and an independent auditing firm were probing an acquisition by its US atomic division Westinghouse Electric, just hours after it missed a deadline to publish its financial results.
A whistleblower had complained that Westinghouse executives exerted "inappropriate pressure" over accounting at the firm, Toshiba said.
Toshiba failed to report its results as scheduled and later said it had requested a one-month extension for submitting the April-December earnings to market regulators.
The revelation comes less than two years after Toshiba -- one of Japan's best-known firms which employs about 188,000 people globally -- was hammered by an embarrassing profit-padding scandal.
JOIN OUR PULSE COMMUNITY!
Eyewitness? Submit your stories now via social or:
Email: eyewitness@pulse.com.gh