Two passengers started throwing haymakers at each other on board a flight Monday from Tokyo to LAX ... and one ended up in handcuffs.
The fight broke out right before an All Nippon Airways flight took off from Tokyo. According to another passenger ... the men were arguing about something when the brawl started. The men threw punch after punch ... even after a flight attendant and other passengers tried to jump in between them.
Once security boarded the plane ... one of the guys yelled, "You think I'm crazy? What about the government?!"
One of the combatants -- a 44-year-old American -- was removed and reportedly choked an airline employee in the terminal. He was arrested for assault.
There must be something in the water ... a little more than a week ago, a brawl erupted between Delta passengers and even the pilot got a shot in.