According to NM, the incident began when the passenger had a disagreement with the port and airport attendants at the boarding gate, due to a situation related to his flight.

According to the Lisbon Metropolitan Command of the PSP, his "behaviour and brusque gestures caused offense to everyone present”, with the man calling the authorities “liars” and using repetitive expletives.

Despite requests to moderate his language, he continued, so the suspect "was verbally warned and then actively resisted being handcuffed”.