Chilean authorities started an investigation into a mid-air plunge by a Latam flight en route to Auckland from Sydney that hospitalized at least 10 people.

Chile’s accident investigation authority is responsible for the probe and has asked New Zealand for help, the Wellington-based Transport Accident Investigation Commission said in a statement Tuesday. The TAIC, as it’s called, said it’s gathering evidence and is seizing the aircraft’s cockpit voice and flight data recorders.

Flight LA800, a Boeing Co. 787 Dreamliner, experienced a “technical event during the flight which caused a strong movement,” Latam Airlines Group SA said Monday. While no one was seriously injured, seven passengers and three crew members were taken to the hospital after the flight landed in Auckland.

Local media reports describe how the aircraft’s sudden drop in altitude sent passengers flying into the roof of the cabin, before they dropped back down to the floor. The airline didn’t specify the nature of the technical event. According to the Sydney Morning Herald, the pilot said his gauges went blank and he was unable to fly the plane.

The Dreamliner is an advanced twin-engine model made in large parts of lightweight composite materials. It’s a bigger model than the 737 Max plane that’s been in the headlines following a Jan. 5 accident when a door plug blew out on an Alaska Airlines flight.