Videos posted on social media show a man on board the flight, threatening staff and yelling “are you a slave to Allah?”.
The plane was diverted shortly after it left for Malaysia, and landed back at Sydney Airport around 4pm.
One passenger on the plane posted on X, formerly known as Twitter, that they had been waiting for over an hour still onboard the plane.
The plane has been isolated at one end of the runway. Sydney Airport confirmed there was an incident and emergency services had responded.
“We are currently supporting emergency agencies in the management of an incident at the airport,” it said on X.
“The airport is operational with flights arriving and departing.”
“Passengers are encouraged to check directly with their airline regarding the status of their flight.”
Image: Getty/ X/ @jawadmnazir