A United Airlines flight departing Newark Liberty International Airport for Guatemala City is rerouted after a passenger allegedly tries to open a cabin door while the aircraft is cruising at about 36,000 feet. Multiple outlets report that pilots and crews respond to the incident as well as a separate assault onboard: the same passenger is accused of attacking another traveler after the attempted door activity. According to air traffic control audio and reporting citing U.S. authorities, the aircraft diverts to Washington Dulles International Airport, where the crew makes an unplanned landing. One account notes that the door attempt occurs at cruising altitude but that the door could not actually open at that height, while other reports focus on the behavior and the resulting diversion. The incident prompts the flight’s diversion and emergency response procedures, with the aircraft landing at Dulles rather than continuing to its original destination. United 1551 is identified in several reports as the flight involved.