Alaska Airlines grounds 737-9 aircraft after midair window blowout on flight from Portland, Oregon

PORTLAND, Ore. -- An Alaska Airlines flight bound for California made an emergency landing in Portland Friday after a panel blew out mid-air.

Our sister station KABC-TV in Los Angeles obtained a photo from passenger Jonathan Torres of Redlands showing a section missing from the side of the plane.

Video recorded by passengers indicated a relatively calm environment inside the aircraft as passengers used the oxygen masks and prepared for the emergency landing. One passenger was overheard saying there was nobody sitting next to the window when it blew out.

Alaska Airlines flight 1282 left Portland and was headed to Ontario International Airport in Southern California.

The plane was diverted after rising to 16,000 feet about about six minutes after taking off at 5:07 p.m., according to flight tracking data from the FlightAware website. It landed again at 5:26 p.m.

"Yes, we are emergency, we are depressurized, we do need to return back. We have 177 passengers," the pilot is heard saying in air traffic control audio.

The plane landed safely back at Portland International Airport with 171 passengers and six crew members on board, according to the airline.

The airline said the flight "experienced an incident this evening soon after departure."

"The safety of our guests and employees is always our primary priority, so while this type of occurrence is rare, our flight crew was trained and prepared to safely manage the situation," Alaska Airlines said in a statement. "We are investigating what happened and will share more information as it becomes available."

The Federal Aviation Administration said the plane landed safely after the crew reported a pressurization issue. The agency said it would investigate.

The Boeing 737-9 MAX rolled off the assembly line and received its certification just two months ago, according to online FAA records.

Boeing said it was preparing to assist with the investigation.

"We are working to gather more information and are in contact with our airline customer," the manufacturer posted on X. "A Boeing technical team stands ready to support the investigation."

The National Transportation Safety Board also said it's investigating and will post updates when they are available.

The Associated Press contributed to this report.