Otto Beisheim, one of the founders of retail group Metro (MEO.DE), committed suicide on Monday after the German billionaire was diagnosed with an incurable illness.

The body of Beisheim, 89, was found near his home in Bavaria, Reuters said. The exact nature of his illness was unknown.

"He was suffering from an incurable disease and departed this life due to the hopelessness of his health situation," a statement from the Otto Beisheim Group said.

The Beisheim Group said there are no immediate plans to sell his 10 percent stake in Metro, the world’s fourth-largest retailer. Beisheim was its third-largest shareholder.

"Otto Beisheim was a pioneer and a legend in the German and international retail world ... with innovation, courage and ambition, he founded one of the world's leading retail firms," Metro said in a statement.

Beisheim’s net worth was estimated at $3.3 billion by Forbes in March 2012, making him the 344th richest person in the world and the 22nd richest in Germany. Beisheim, a widower, whose wife, Inge Beisheim, died in 1999, had no children. Reuters said his assets will be divided between two foundations to foster cultural and business projects.

According to Metro, Beisheim introduced Germany to the cash-and-carry concept, a type of wholesale from which goods are sold in bulk to trade customers.

"He revolutionized the sector in the mid 1960s," Metro Chief Executive Olaf Koch said in a statement.

Beisheim created the first cash-and-carry store in Muelheim an der Ruhr, in western Germany, in 1964, after its success in the U.S., before taking his concept throughout Europe and then abroad to China.

Beisheim was a member of Adolf Hitler’s Waffen-SS, though the Beisheim Group said he was a low-ranking member of the regime and moved divisions in 1942.