Japanese video game maker Nintendo has said its chief executive Satoru Iwata has died of cancer at the age of 55.
Mr Iwata underwent surgery last year and had resumed his duties after a brief period of recovery.
He is a highly revered figure in the Japanese gaming scene and considered the leading figure behind Nintendo's successful turnaround after he joined the company in the year 2000.
Most recently, he led Nintendo into the rapidly growing mobile gaming sector.
Mr Iwata started out as a programmer in a Nintendo subsidiary in the 1980s and became president of Nintendo in 2002.
Under his leadership, the company launched its hugely successful Wii and Nintendo DS consoles and he is considered the crucial driver behind the focus on easy-to-use consoles, a move that allowed the company to tap into a much wider audience beyond the traditional gaming community.
Mariko Oi, BBC News
Growing up in Japan in the 1980s, Super Mario was a gaming character that you couldn't avoid. But as the gaming population started to decline in the late 90s, Mr Iwata knew that he needed to make products that were more appealing to non-gamers.
And he succeeded. Nintendo DS quickly became the world's best-selling handheld game console when it was released in 2004.
Two years later, there came another successful launch of Wii which was dubbed the computer game that even your grandma can play. Together, they switched on millions of new converts to computer games.
But the rise of mobile phone games has posed a serious threat to Nintendo and some investors questioned his decision not to enter the market sooner.
As he put it himself, Mr Iwata was a chief executive who had the brain of a games developer and the heart of a gamer.
Tributes have been coming in on social media with the team at PlayStation saying: "Thank you for everything, Mr. Iwata."
One user @BrandonNobbs tweeted: "Nintendo might not be the most profitable company, but it's always made games with a heart. #ThankYouIwata #Nintendo."
His death comes as Nintendo expects to double its annual operating profit based on the long-awaited entry in the rapidly growing smartphone gaming sector to counter weakening sales of its traditional consoles.
Last year, Mr Iwata said he would halve his salary for several months after the company was outpaced by rivals Sony and Microsoft in console sales.
Nintendo shares dropped 0.7% in early Monday trading.
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