A Southwest Airlines jet was forced to turn back and make an emergency landing at LAX after a male passenger allegedly began choking a woman because she reclined her seat, witnesses said.

Flight 2010, bound for San Francisco, turned around  late Sunday night about 30 minutes into the journey because of a “rapidly escalating situation involving passengers who were not traveling together,” the airline said in a statement.

"Flight 2010, declaring an emergency," the pilot says in audio from the flight. "Evidently we've got two passengers that are in a physical altercation."

Witnesses reported the woman said a man sitting behind her tried to strangle her because she put her seat back, NBC News said.

The unidentified man was detained by Los Angeles Airport Police, but no arrests have been made, Los Angeles FBI spokeswoman Laura Eimiller told INSIDE EDITION.

The remaining passengers boarded another flight and arrived in San Francisco five hours late.

The International Air Transport Association says it costs an airline about $200,000 every time a flight is diverted.

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