TOKYO (AFP) - Toshiba shares plunged more than 16 per cent Monday after the Japanese conglomerate withdrew its earnings forecast and said it won't pay a dividend, citing a probe into accounting irregularities on infrastructure projects.

Toshiba, whose shares faced massive selling at the start, tumbled to the day's limit low of 403.3 yen, down 16.55 per cent, or 80.0 yen.

Shortly after the Tokyo market closed on Friday, Toshiba announced it had cancelled its projection for a 120 billion yen (S$1.33 billion) net profit on sales of 6.7 trillion yen in its latest fiscal year to March.

The vast engineering conglomerate, which makes everything from batteries to nuclear reactors, also warned it may also have to revise past earnings.

It said it would hire an outside team of experts to look into the matter after finishing an internal investigation.

The company said it underestimated the cost of "certain" infrastructure projects along with other accounting irregularities, but did not elaborate further.

The firm said it won't report its revised fiscal-year results until at least next month.