A hospital has announced that Mustafa Koc, the chairman of Turkey's top industrial conglomerate, has died. He was 55.

The American Hospital in Istanbul said Koc died Thursday after suffering a heart attack at home. Media reports said he was taken ill while exercising.

Koc had been head of Koc Holding — whose interests range from the automotive sector to durable goods and energy — since 2003.

He took over the company from his father Rahmi Koc, the 84-year-old patriarch of the Koc family — one of Turkey's wealthiest. The company was founded in 1926 by Mustafa Koc's grandfather, Vehbi Koc, who died in 1996.

Mustafa Koc is survived by his wife Caroline and two daughters.