A United Airlines flight bound for Spain from Newark Liberty International Airport turned around midflight Saturday due to a possible security threat.
United and Alaska airlines are canceling more flights nationwide until all Boeing 737 Max 9 jets are inspected.
A midair window blowout prompted some Boeing planes to be grounded, causing cancellations and delays at O'Hare Airport.
Lianne Mandelbaum said she felt "threatened" after she spoke to flight crew.
About five people jumped and tackled the suspect, saying they pulled a broken spoon, which he allegedly turned into a weapon, out of his hand.
A San Francisco-bound flight that plunged toward the Pacific Ocean last December will be investigated by National Transportation Safety Board.