Dhirubhai Ambani, who rose from humble beginnings to become the billionaire founder of India's largest business empire, died on Saturday, 12 days after suffering a second stroke.

The death of Indian business legend has brought to an end a watershed chapter in the nation's corporate history, newspapers and market analysts said.

Ambani, who established Reliance, a group with a market value of $9 billion, died in the intensive care unit of Bombay's Breach Candy Hospital.

He was rushed there on June 24 after suffering his second stroke in 16 years. A stroke in 1986 left the barrel-chested, plain-speaking Ambani partially paralysed.

Ambani ranked 138th on the latest Forbes magazine list of the ultra-rich with a fortune of $2.9 billion.

India's great and powerful - politicians, industrialists, business leaders and Bollywood idols - had flocked to the hospital over the past two weeks upon hearing he was in a critical condition.

The news also caused Reliance group share prices to slide in what analysts described as a knee-jerk response to concern over prospects for the industrial empire he had built from scratch.

Analysts dismissed such concern, noting his two sons - Stanford University- educated Mukesh and Wharton School of Business graduate Anil - have run the day- to-day operations of the conglomerate for years.

Ambani was born in 1932, the third of five children of a poor school teacher in a rural Indian village.

At 17 he left home to join his eldest brother in Yemen, where he worked as a petrol station attendant, and later a clerk for a local affiliate of Burmah Shell, all the while dreaming - according to the legend - of one day owning an oil company.

He achieved that and more.

Ambani created an industrial empire which includes Reliance Petroleum, which operates the fifth-largest refinery in the world, and Reliance Industries, a huge synthetic fibre and petrochemical maker.

The two companies are merging, creating one of the world's 30 largest energy companies.

Recently Reliance has also branched out into biotechnology and telecommunications. It is investing $5 billion to become the world's only fully integrated communications company.

And Reliance Biotechnology's stem cell cultures were last year designated by the U.S. government as one of only a handful worldwide suitable for research purposes.

Ambani transformed the way Big Business operates in India.

To finance his grand ambitions, Ambani raised money through the market, ending the near monopoly on bank financing in India doled out to a small clique of elite families.

"Through his promotion of the equity cult and his world vision of manufacturing, Ambani impacted the economy as no businessman has done," Gita Piramal wrote in her book Business Maharajas about seven of India's most powerful tycoons.

Reliance's phenomenal growth made millionaires of thousands of middle-class Indians, fuelling the growth of an investment culture in a nation just emerging from a half century of socialism and central economic planning.

One newspaper lauded Ambani for teaching "the country's blue-blooded industrialists that to create wealth one must first learn to share it."

But Reliance's remarkable growth also prompted accusations that Ambani's success owed as much to manipulation of government policy as to shrewd business decisions.

"The corporate world is sharply divided between those who feel he is a visionary and those who consider him to be a manipulator and a crook," wrote Piramal.

Ambani attributed those attacks to his lowly beginnings.

"Controversy is the price to be paid for success," he told one interviewer. "You must understand human psychology. Because, not so long ago, I was just a riff-raff boy and people would say: 'Who is this Dhirubhai? He was merely a hawker who used to wait outside my office.'

"This is the truth and I am not ashamed of that. My skin, fortunately, is very thick! However, the fact remains that when an elephant walks, dogs tend to bark."