A preliminary investigation has found that a sudden strong gust of wind led to a fatal paragliding accident in Shek O last month.

According to the Air Accident Investigation Authority, at about 2pm on December 9, a 68-year-old paraglider pilot went alone to the take-off field in Shek O Country Park.

An investigation report released on Wednesday said the man was preparing to fly and untangling the suspension lines. It said the paraglider was partly inflated by the wind but was still on the ground. The pilot was not wearing a helmet and was not strapped into his harness.

Around 40 seconds later, a sudden strong gust further inflated the paraglider and lifted both the paraglider and the pilot off the ground. At that moment, his left hand held the right riser and his right hand held the left riser, the report said.

About 10 seconds after becoming airborne, the left riser slipped from his grasp, and the paraglider started to collapse. A few seconds later, he fell onto the hillside with the paraglider.

Hikers alerted the police. The pilot was airlifted by a Government Flying Service helicopter to Eastern Hospital where he was pronounced dead shortly before 4pm. The investigation is ongoing.