A United Airlines flight bound for Chicago was forced to make an emergency landing in New Mexico after a passenger's video captured what appeared to flames shooting out by one of the engines.

Flight 366 passenger Thomas Chorny recorded and later tweeted video of the shocking incident early Monday. The plane had departed from San Diego, California, late Sunday.

In his tweet, Chorny wrote, "Strange to sit there & think 'What if this is it?'" He went on to say that though he was extremely nervous, he didn't feel the need to panic others.

Strange to sit there & think ‘What if this is it?’ To just sit there & accept the potential fate that seems to be a possibility & not tell the sleeping people all around you. No need to panic the others. I’m a pretty calm person but took me a while to stop the shakes & trembles. pic.twitter.com/4rWfNvFhBM — Thomas Chorny (@SteepleCoach) December 16, 2019

"They were bumps that felt like turbulence and when I looked out the window, I saw flames shooting from the right engine," Chorny told NBC News. "It was definitely unsettling."

"They shut the engine down to idle and the flames went out, then we started banking left and went down to a much lower altitude, so I knew that they were taking some kind of action in response."

After about 10 minutes, he says, flight crew announced the flight would be diverted to Albuquerque, New Mexico.

Chorny said he notified the airline about the flames he saw by the engine.

The incident was attributed to "a mechanical issue with one of the engines," a United spokesperson told NBC News. "The flight landed safely, and customers deplaned normally at the gate. Our maintenance team in Albuquerque will inspect the aircraft."

United Airlines arranged for another plane to take the passengers to Chicago.