A man arrested by armed police in a secure part of Norwich International Airport had been released from jail on licence, police have confirmed.
The 31-year-old, from London, allegedly assaulted two people in a hangar before verbally threatening a third person at 02:30 BST on Tuesday.
He was arrested on suspicion of assault but was deemed unfit to be interviewed after a mental health assessment
The man has been taken to HMP Norwich.
A Norfolk Police spokesman said: "This is not being treated as a terror-related incident and police are not looking for anyone else in connection with it."
Police said a man entered a hangar and approached two workers, assaulting one with a mug and another with what is believed to be a piece of broken glass.
The men suffered minor cuts and bruises, which did not require medical treatment.
The suspect then approached a stationary lorry and entered the cab before verbally threatening a member of security staff who was nearby.
Officers arrived and detained the man. The vehicle was not driven by the suspect, police said.
The incident did not affect any public areas of the site and the airport remained open with flights operating as normal.
Detectives are keen to speak to any witnesses or anyone who saw a man acting suspiciously in the area at the time.