New video footage has emerged showing the moments leading up to the altercation that occurred on United Airlines flight 3411 on Sunday.

The clip, taken by fellow passenger Joya Griffin Cummings, shows a passenger, who has been identified as Dr. David Dao, speaking to security personnel who are telling him to deplane after the airline overbooked the flight.

“I won’t go, I’m a physician I have to work tomorrow, 8 o’clock…” Dao says......