The helicopter that crashed, killing basketball great Kobe Bryant, his daughter and seven others, was not certified to fly in foggy conditions.
According to officials, Island Express Helicopters, which owned the Sikorsky S-76B that crashed, was allowed to operate under visual flight rules.
"The preliminary information is Island Express' 135 certificate did not allow for IFR flight," said Keith Holloway, a National Transportation Safety Board spokesman. "No other specifics are available at this time."
Preliminary investigations have pegged foggy weather conditions as a possible cause for the crash.
Meanwhile, the Lakers played their first game since Bryant's death, and paid tribute to the star by wearing his numbers - 8 and 24 - during warm-up. They went against the Portland Trail Blazers at the Staples Center in LA.
Israeli Prime Minister Benjamin Netanyahu said on Sunday Israel would determine which foreign forces it would allow as part of a planned international force in Gaza to help secure an end to its war under US President Donald Trump's plan.
Two suspects in the brazen daylight heist of some of France's crown jewels from the Louvre were arrested in Paris on Saturday evening and are being questioned, Le Parisien newspaper reported on Sunday, citing sources close to the investigation.
Ukraine's President Volodymyr Zelenskyy called for new strong sanctions against Russia and its allies after Russian drones killed three and injured 31, including six children, in an overnight air attack on Kyiv.
The outlawed Kurdistan Workers Party (PKK) said on Sunday it was withdrawing from Turkey as part of a disarmament process it is coordinating with the government, and pressed Ankara for concrete measures to move the process along.