Passengers at Perth Airport Terminal 1 are experiencing disruptions, as the Australian Federal Police and WA Police investigate a reported unattended bag at the terminal.

The AFP have urged the public to “avoid the area and await further advice”.

In a statement released at 4:30pm local time, a spokesperson for the airport said  an exclusion zone had been set up.

“An unattended item is currently being investigated by the Australian Federal Police and Western Australia Police at Perth Airport,” the statement read.

The silhouettes of two people inside a Perth Airport terminal with Virgin planes outside the window.

Perth Airport is located about 12km east of the CBD.  (AAP: Richard Wainwright)

“As a precaution, an exclusion zone has been established in the area.

“The T1 forecourt pick-up and drop-off road has been temporarily closed while police conduct their investigation.

“Passengers can conduct drop-off and pick-up activity from the T1 short term car park.”

Crowds could be seen gathering outside the terminal entrance, with several flights impacted, according to passengers who spoke to the ABC.

One interstate traveller, Austin, said he saw groups of people standing outside the terminal when he arrived for his flight.

“I just heard [my flight’s] delayed and the terminal’s closed, hoping to get an answer soon,” he said.

Passengers are also advised to check the Perth Airport website for updates.