An altercation at gate C30 at DFW airport. It appears that a man, possibly under the influence of drugs, takes a dislike to another man whom he assumes to be gay. It looks like the alleged gay man then takes a picture of the man harassing him. Then things escalate. When things turn violent several members of the public step in immediately to prevent it going any further.
It appears that one member of the public was injured, possibly breaking his ankle (listen for the noise 1 minute and 22 seconds into the video). He appears to be walking fine when he intervenes but later is seen in a wheelchair with one shoe removed.
One of the passengers who intervened has been identified as actor Paul Rudd who stared in films such as Anchorman and The 40-Year-Old Virgin, and TV shows such as Parks and Recreation.
Update Oct 27th: Paul Rudd denies that he was one of the passengers who intervened, another story, and another story. But in this story the denial is still questioned.