(Seoul) Lee Kun-hee, who built Samsung Electronics into a global powerhouse in smartphones, semiconductors and televisions, died on Sunday after spending more than six years in hospital following a heart attack, the company said.

The charismatic leader of Samsung Group and the country's richest person, grew it into South Korea’s biggest conglomerate. But he and the empire he built have also been vilified by critics for wielding huge economic clout, and for opaque governance and dubious transfers of the family wealth.

"Lee is such a symbolic figure in South Korea's spectacular rise and how South Korea embraced globalisation, that his death will be remembered by so many Koreans," said Chung Sun-sup, chief executive of corporate researcher firm Chaebul.com.

Lee, who was 78, is the latest second-generation leader of a South Korean family-controlled conglomerate, or chaebol, to die, leaving potentially thorny succession issues for the third generation.

Lee's "innovative leadership and indomitable spirit should be highly regarded in any era and in any field," ruling party leader and former prime minister Lee Nak-yon wrote on Facebook.