Updated

A Chinese hotel magnate is believed to be among the dead after a helicopter taking him on a tour of his newly-bought French vineyard crashed into a river Friday.

Lam Kok, 46, had just completed the purchase of the 160-acre Chateau de la Riviere, a major vineyard in the Bordeaux wine region of France estimated to be worth approximately $41 million, and was making a tour of the grounds with the vineyard's previous owner, James Gregior; an interpreter; and Kok's 12-year-old son.

Emergency workers located the helicopter's wreckage in the Dordogne River Saturday morning after receiving a phone tip from someone who had seen the helicopter go down. The body of Kok's son was found inside. However, the other three passengers had not been found by the time the search was suspended for the evening.

French police said that the Dordogne's strong currents were making the recovery operation difficult.

Sky News reported that Kok's wife was supposed to go on the tour with her husband, but had begged off at the last minute, citing her fear of helicopters.

Kok is the head of the Hong Kong-based Brilliant hotel group, which said it had wanted to turn the vineyard into a luxury tea and wine tasting center with a planned hotel nearby.

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