Southwest flight 2010 had to return and make an emergency landing at Los Angeles International Airport, California, on October 18.
According to the airline, the plane was heading to San Francisco when the the pilot declared emergency due to a physical altercation between two passengers. Some sources reported that a male passenger choked a female passenger after she reclined the seat in front of him.
The plane landed safely. The male passenger was taken in by FBI agents for questioning.
The airline arranged an alternate plane for the remaining 136 passengers.

GoAir flight G8-329 had to make an emergency landing in Delhi, India, on February 14th.
Air Arabia flight G9824 had to return for an emergency landing at Ras Al Khaimah International Airport, United Arab Emirates, on February 26th.
Japan Airlines flight JL-6 made an emergency landing at Tokyo International Airport, Japan, on September 5th.