US authorities announced on Monday an investigation into a weekend flight to Hawaii that left 11 people with serious injuries after the plane encountered major turbulence. The US National Transportation Safety Board (NTSB) “is investigating the Dec. 18 air turbulence incident on the Hawaiian Airlines flight from Phoenix to Honolulu which resulted in serious injuries,” the board said on Twitter. The incident happened as severe turbulence hit a flight from Phoenix to Honolulu Sunday, injuring at least 36 people, 11 of them seriously, authorities announced. “Medical care was provided to several guests and crew members at the airport for minor injuries while some were swiftly transported to local hospitals for further care,” Hawaiian Airlines said in a statement.Hawaiian Airlines Chief Operating Officer Jon Snook said the airline will do a thorough investigation of the plane in order to fix components in the cabin. Video posted to social media appeared to show widespread damage to the cabin, and several individuals, including passengers and crew members, with significant injuries.