PORTLAND, Ore. (KOIN) — CBS News aviation correspondent Kris Van Cleve arrived in Portland as the NTSB investigation into the Alaska Air accident when a door blew off at 16,000 feet shortly after takeoff last Friday.

He spoke with KOIN 6 News prior to a second NTSB press conference Sunday evening and said there are some “red flags” about this particular aircraft that are now known.

But he said there are a lot of questions the NTSB must answer before any determination is made.

Watch the video below for his complete comments.

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