SYDNEY >> As officials investigate what caused a “strong shake” before a sudden plunge on a plane traveling between Australia and New Zealand, a passenger on Tuesday described a wild ride, with people without seatbelts thrown from their seats and some crashing into the plane’s ceiling.

At least 50 people were injured Monday by what LATAM Airlines described as a “strong movement” on the Chilean plane traveling from Sydney to Auckland, New Zealand.

The Boeing 787-9 Dreamliner later landed at Auckland Airport as scheduled and was due to continue on to Santiago, Chile.

“The plane, unannounced, just dropped. I mean it dropped unlike anything I’ve ever experienced on any kind of minor turbulence, and people were thrown out of their seats, hit the top of the roof of the plane, thrown down the aisles,” passenger Brian Jokat told ABC news in Australia on Tuesday.

“Some of the roof panels were broken from people being thrown up and knocking through the plastic roof panels in the aisle ways. And there was blood coming from several people’s heads.”

LATAM Airlines said in a statement that there was “a technical event during the flight which caused a strong movement.” In a later statement, the airline said that the plane “experienced a strong shake during flight, the cause of which is currently under investigation.”

The airline said it was working with officials to support an investigation into what happened.

Passengers were met by paramedics and more than 10 emergency vehicles when the flight touched down in Auckland.

About 50 people were treated at the scene for mostly mild injuries, while 13 were hospitalized, an ambulance spokesperson said.

LATAM said that of the 13, the majority were discharged soon after, and only one passenger and one cabin crew member needed additional attention, “but without any life-threatening risks.”

Passengers said a number of people weren’t wearing seatbelts when flight LA800 suddenly dropped.

“If you were in your seat, you went straight up to the ceiling and bounced off the roof. I just happened to be one of the lucky ones who was strapped in for that incident,” Jokat told ABC.

He said that he woke up suddenly during the drop and found the passenger who’d been next to him “on the roof of the plane.”

The airline said that it “regrets the inconvenience and injury this situation may have caused its passengers, and reiterates its commitment to safety as a priority within the framework of its operational standards.”