CNN  —  United Airlines crew and passengers had to stop what court documents describe as an unprovoked beating of a man on a flight on Monday. A criminal affidavit alleges that as Everett Chad Nelson was walking back from the bathroom about two hours into the flight, he stopped at seat 12F and “began physically attacking a sleeping male passenger.” Nelson punched the still-unidentified man “repeatedly in the face and head until blood was drawn,” court documents say, adding the incident “lasted