FAA to probe Boeing after door plug detached mid-flight, left gaping hole in Alaska Airline jet

The Federal Aviation Administration said Thursday the agency has opened a probe on aircraft manufacturer Boeing after a door plug on one of its commercial jets used by Alaska Airlines recently detached mid-flight, leaving a gaping hole in the fuselage. 

"This incident should have never happened and it cannot happen again," said agency said in a social media post.

The faulty plug, inserted in the fuselage instead of an exit door, was on a Boeing 737 Max 9.

The plug fell off a few minutes after Alaska Airlines Flight 1282 took off Friday from Portland International Airport, according to ABC News. 

The incident depressurized the cabin and exposing passengers to open air thousands of feet above ground.

Boeing said it will "cooperate fully and transparently with the FAA and the [National Transportation and Safety Board] on their investigations."

The FAA also said Thursday that all Boeing 737 Max 9s with a plug door will remain grounded until the administration determines whether each can safely return to operation.

The grounding impacts roughly 171 planes worldwide, ABC also reports.