He will be succeeded by chairman Masashi Muromachi, with vice-chairman Norio Sasaki also stepping down.

On Monday, an independent panel appointed by Toshiba said the firm had overstated its operating profit by a total of 151.8bn yen ($1.22bn, £780m).

The overstatement was roughly triple an initial estimate by Toshiba.

The company's business empire stretches from home electronics to nuclear power stations.

'Deeply apologise'

"It has been revealed that there has been inappropriate accounting going on for a long time, and we deeply apologise for causing this serious trouble for shareholders and other stakeholders," the company said in a statement.

"Because of this Hisao Tanaka, our company president, and Norio Sasaki, our company's vice chairman... will resign today."

Mr Tanaka told a media conference that "we have a serious responsibility", adding that the company would need to "build a new structure'' to reform itself.

Mr Tanaka, 64, and Mr Sasaki, 66, both joined Toshiba in the early 1970s.

Mr Sasaki served as Toshiba president between June 2009 and June 2013, covering most of the period during which the firm inflated the profits.

Atsutoshi Nishida, an adviser and former chief executive from 2006 to 2009, also gave up his post.

Mr Tanaka and his predecessors are among eight high-level executives who have now resigned after the independent report found senior management involved in a scheme to inflate profits over several years.

People took to social media to express their concern at the scandal.

One twitter user remarked "It's appalling how long this cover up could have carried on", while another said "clean out the entire company! Toshiba needs to carry on its legacy properly."

He also said it was the most damaging episode in Toshiba's 140-year history. The company was created by a merger in 1938, but its roots date back to 1875.

'Very regrettable'

Toshiba's accounting scandal began when securities regulators uncovered problems as they probed the company's balance sheet earlier this year.

One line that the investigators looked into was that executives set unrealistic targets for new operations after worries that the 2011 Fukushima disaster may hit Toshiba's nuclear division.

While the report did not specifically refer to Fukushima, it did say that pressure within Toshiba was strong in the accounting years of 2011 and 2012.

The findings mean Toshiba will have to restate its profits for the period between April 2008 and March 2014. It is unclear whether it will affect the company's results for the year ending March 2015.

The finance minister, Taro Aso, said the case could undermine confidence in corporate governance in Japan.

(BBC)