The National Transportation Safety Board (NTSB) says an initial investigation into the Kobe Bryant helicopter crash shows no clear evidence of engine failure.
On Saturday (NZ time), the NTSB released their preliminary report into the crash which killed NBA legend Bryant, his 13-year-old daughter Gianna and seven others in Calabasas, California last month.
The group was flying to a girls basketball tournament at his Mamba Sports Academy. Gianna's team was coached by Bryant and was playing in the tournament.
Officials said the chopper, which was flying using only visual readings, slammed into a hillside amid foggy conditions, but the NTSB won't be able to confirm if heavy fog was to blame until the final report is released for at least a year.
"The entire fuselage/cabin and both engines were subjected to a post-crash fire," the report said. The cockpit was highly fragmented.
"The instrument panel was destroyed and most instruments were displaced from their panel mounts. Flight controls were fragmented and fire damaged."
The report adds that the impact of the crash was so severe, it formed a two-foot-deep crater on the brushy hillside. A tree branch about 30 feet away was sliced cleanly in three different spots.
The Sikorsky SK 76B was falling towards the ground at 4,000 feet per minute before crashing.
At this stage, the victims' deaths have been ruled an accident by blunt trauma, according to the Los Angeles County coroner.
Meanwhile, Bryant's widow, Vanessa, announced that a "celebration of life" memorial will be held on February 24 at the Staples Center, honouring her late husband and daughter.