The National Transportation Safety Board (NTSB) has launched a team to investigate the Alaska Airlines flight that was forced to make an emergency landing when a part of the aircraft blew out mid-trip.

“NTSB has launched a Go Team to Portland, Oregon to investigate an event with a Boeing 737-9 MAX during a flight from Portland to Ontario, California,” the agency announced on X Saturday morning.

“The team will arrive on scene later today and consists of experts in structures, operations, and systems. Chair Jennifer Homendy will be the spokesperson on scene,” the NTSB post added.

The Alaska Airlines flight took off from Portland International Airport around 4:52 p.m. local time Friday, but reversed course just a short time later.

The aircraft carrying 171 passengers and six crew members “experienced an incident,” Alaska Airlines said in a statement afterward, without giving further information.

Passenger’s cell phones and other belongings were sucked out the gaping hole in the side of the cabin, those on board said.

One child even had to be held down in his seat by his mother to keep him from being pulled away, one witness told KPTV.