Alaska Airlines has grounded all its Boeing 737 Max 9 aircraft after an emergency landing of one of its planes yesterday, Friday, in Oregon in the northwest United States, after 177 passengers reported that one of the windows came off its place following takeoff.

The Federal Aviation Administration explained via the "X" network that the plane took off on flight number 1282 from Portland International Airport around 5 p.m. (1 a.m. Saturday GMT) before returning safely "after the crew reported a pressure issue."

Photos published on social media showed a detached window on a plane with oxygen masks hanging from its ceiling.

The CEO of Alaska Airlines, Ben Minicucci, said in a statement, "After what happened tonight on flight 1282, we decided to take a precautionary step by temporarily grounding our fleet of 65 Boeing 737-9 aircraft."

He added, "Each aircraft will return to service after maintenance and a full safety inspection," expecting to complete this within a few days.

One passenger named Kyle Renker told the American television station CNN that the window was torn off immediately after takeoff.

He said, "It was really surprising. The plane had barely taken off when the window pane came off, and I only noticed when the oxygen masks dropped."

Another passenger named Vi Nguyen told the American newspaper The New York Times that she woke up due to a loud noise during the flight.

She said, "I opened my eyes, and the first thing I saw was the oxygen mask right in front of me, then I looked to the left, and the side window was gone."

She added, "The first thing that came to mind was that I was going to die."

The National Transportation Safety Board, the Federal Aviation Administration, and Alaska Airlines announced they are investigating the incident.

The company stated that "the plane returned safely to Portland International Airport with all 171 passengers and six crew members on board."

It confirmed that "the flight crew was trained and prepared to safely handle this situation, despite the rarity of such incidents."

The specialized site "FlightAware" indicated that the plane, a Boeing 737 Max 9, took off at exactly 5:07 p.m. local time, heading to Ontario, California, and returned to the airport after about 20 minutes.

The plane had been certified in October, according to Federal Aviation Administration records available online.

The American aircraft manufacturer Boeing wrote on "X" that it is working to gather more information, and that a technical team is at the disposal of investigators.