Hundreds have come out to mourn Kobe Bryant, the world-famous retired US basketball player who died when his private helicopter crashed on a hillside in California on Sunday.

Investigators are working to find out what caused the helicopter crash that killed nine people, including Bryant and his 13-year-old daughter Gianna.

Weather conditions at the time of the crash, which included heavy fog and poor visibility, as well as the helicopter pilot’s decision to fly by special visual flight rules, may be key areas of the investigation.

Al Jazeera's Rob Reynolds reports from Los Angeles in the US state of California.

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