The helicopter crash in France that killed Hong Kong-based tycoon Kok Lam and three others might have been caused by the aircraft running out of fuel, according to a report.
An error by the pilot James Gregoire could also have led to the December 20 accident, public broadcaster France 3 said, citing sources close to preliminary investigations.
The body found last Saturday near the crash site but not yet identified was almost certain to be one of the two Chinese passengers - either Kok or his interpreter and financial adviser Wang Peng - it added.
Gregoire told an engineer who had just completed a regular maintenance check 48 hours before the crash that the helicopter needed refuelling.
But apparently it was not refuelled and the two tanks - one 120 litres and another 70 litres in volume - were left almost empty when he took Kok, Kok's 12-year-old son, Kok Shun-yu, and Wang on a celebratory aerial tour of a chateau estate that the Chinese businessman had just bought from Gregoire, the report said.
The engineer changed the helicopter's battery and revised its trim tabs, which help stabilise the aircraft, in the maintenance check.
Human error may also have been to blame for the accident, as the engineer told Gregoire after a test ride following the maintenance check that he had flown "too close to the rushing waters" of the River Dordogne. He also told him he was taking risks, as there were no floats on the helicopter.
Ongoing investigations suggested the body that was found last Saturday had dental features that seemed Asian, the report said.
An autopsy performed on Monday did not establish the cause of death, since the body had been in the water too long. DNA tests were under way and results would come out this weekend, the report said.
Search efforts have been continuing to find the remains of Kok, a 46-year-old tea-and-property magnate, Wang and Gregoire, a French entrepreneur. The only body recovered so far is that of Kok Shun-yu, found a day after the crash inside the wrecked helicopter, of a type widely used by police and armed forces.
Kok and his wife had just bought the Chateau de la Riviere and its 65 hectares of vineyards for a reported €30 million (HK$318 million).