Karl-Erivan Haub, the CEO of the German retail group Tengelmann and one of the richest men in Germany, has disappeared during a routine skiing excursion in the Alps along the Italian-Swiss border, and though an extensive search operation is underway, his family members are fearing the worst.

Haub, who has led the German retail group since his father passed away unexpectedly in March 2000, has been described by family members as an avid Alpine skier. He was vacationing at a ski lodge near the Matterhorn when he didn't show up for a meeting at a hotel in the Zermatti resort after taking a lift up the mountain earlier in the day. His family promptly notified police of his disappearance, per USA Today.

Poor visibility and the threat of an avalanche have hindered the search operation - much to Haub's family's dismay.

Haub was in Switzerland to train for the Patrouille des Glaciers ski race, a popular ski race organized by the Swiss army that was set to begin April 17.

In a letter to Handelsblatt, a German newspaper, the businessman's brother, Christian Haub, wrote that Karl-Erivan was "a very experienced alpinist and skier" and that despite all the time that had elapsed since his disappearance, he hoped his brother would be found.

"Of course our family is prepared for such a situation," Christian Haub said. If Karl-Erivan doesn't return alive, "the business will continue to run smoothly and orderly," Christian Haub promised.

Haub's company, Tengelmann, is a major force in the German retail sector. With 73 holdings generating some €30 billion ($37 billion) in revenue, its owns businesses including hardware store Obi and textile discounter Kik.