Melbourne airport plunged into 'total shutdown' with bomb squad called in and terminal evacuated

Avalon's domestic terminal was evacuated entirely, while Victoria Police confirmed an individual had been detained.

Police also said they were carrying a "safety check" at the airport.

Images from the travel hub showed queues of traffic backed up outside the airport as it was shut off to the public.

Avalon primarily serves domestic traffic, with Australian airline Jetstar running flights to Adelaide, Brisbane, Gold Coast and Sydney.

But the shutdown was put in place shortly after 6am (9pm BST), sparking travel chaos just as commuters were hoping to jet off.

Passengers landing from tourist hotspot Bali were escorted off their plane and into a holding area, according to local outlet 9News.

One prospective traveller hoping to fly out of Avalon, Lisa, said the entrance was blocked when she arrived.

"We arrived at the airport around 7am (10pm BST) and they had just put up the closure," she told ABC Radio Melbourne.

"No one sort of knew what was going on.

"We knew something was fairly significant because there were a lot of police cars and other sort of cars going into the airport."

Another witness, David, told 3AW how people had walked out of the airport on foot - and that the terminal had been left in a state of "total shutdown".

"The whole area is closed," he said. "They've blocked us off, but no one's telling us a thing."

International flights will continue to be processed as normal, a spokeswoman for Avalon confirmed.

"The domestic terminal at Melbourne Avalon Airport was evacuated this morning following the identification of a suspicious item during the screening process," she said.

"Victoria Police attended and an individual has been detained.

"At this stage, passengers are being advised that, due to safety precautions, delays are expected to the Brisbane flight this morning.

"We will provide further updates regarding any additional delays as more information becomes available."