Sydney Airport has been thrown into chaos after an incident in the control tower sparked evacuations and delays to flights.
Smoke is understood to have been coming from the control tower early on Sunday morning.
The incident prompted flights to be grounded while inbound planes already in the air were diverted.
Sydney Airport has been thrown into chaos after an incident in the control tower sparked evacuations and delays to flights
Frustrated travellers vented their anger online amid early reports the delays had been caused by a fire.
'On flight from #Canberra to #Sydney and just been informed by flight staff that there has been a fire in the tower at Sydney airport,' one wrote.
'Everything is on hold!! No idea how long the delays. Do I get to Perth today??'
Another added: 'Not a great start to my Tampa trip. Flight from Gold Coast to Sydney has been grounded due to #sydneyairport control tower evacuation.
'Unlikely I'll make my multiple connections.'
A third person wrote: 'Control tower at Sydney Airport apparently evacuated.
'Flights grounded and diverted. May as well get comfortable as we wait to find out when we'll be leaving Ballina.'
The incident is understood to have come under control later in the morning with flights already resuming.
Daily Mail Australia contacted Air Services Australia for comment.
More to come