Reclined Seat Leads to Fight, Emergency Landing on LAX-SFO Flight

Updated, 2:35 p.m.

A Southwest Airlines jetliner on its way to San Francisco returned to Los Angeles International Airport shortly after takeoff on Sunday because of a fight between two passengers, reportedly because of a reclined seat.

FBI agents met the plane at the gate late Sunday and one person was removed from the Boeing 737, Southwest spokeswoman Melissa Ford told The Associated Press.

The pilot of Flight 2010 -- which was already nearly 2½ hours late in departing -- decided to return to LAX because of a "rapidly escalating" situation, Ford said Monday. The incident involved a "physical altercation by one person against another," Ford said Monday. She did not elaborate but said the two passengers involved were not traveling together.

Here's how NBC Bay Area describes the altercation:

[A] passenger, identified as Melanie, posted a photo on Instagram and described in German what she saw. ...

Melanie wrote that she saw a man "strangling a woman because she tilts her seat back" and nine "cop cars" met the plane when it landed.

In a separate interview, she also told NBC News that she saw a woman push her seat back to recline and then the man who was sitting behind her “started choking her. She shouted for help and the crew came to see what happened. The man stayed very calm during the whole situation.”

The passenger who was removed from the flight was detained for questioning. No arrest was immediately made but the investigation was still underway, FBI spokeswoman Laura Eimiller said.

"The allegations involved the reported assault of a fellow passenger," she said.

The flight left LAX around 9:50 p.m. and returned to the airport about an hour later, Ford said. The captain declared an emergency to receive priority for landing, she said.

The remaining 136 passengers switched planes and departed again for SFO. They arrived around 1:50 a.m. Monday.