A security alert at Melbourne's Tullamarine Airport forced the evacuation of a terminal building and disrupted some flights late last night.
Authorities said a security threat was made against Tigerair and the airline's terminal was closed at about 9pm (AEDT) while police officers carried out a search, the ABC reported.
The terminal was evacuated to allow the check to be completed, a police spokesperson said.
An airport spokesperson said some Tigerair flights were disrupted but all other operations were continuing as normal.
According to Melbourne Airport's website, seven Tigerair flights were due to land at the airport after 9pm.
Scott Marquardt, who said he was on board a Tigerair flight from Brisbane that landed about midnight, tweeted saying the crew had announced they would be on the tarmac for at least an hour.
He also tweeted that passengers were told some planes were disembarking but "we'll be on ours for a lengthy amount of time".
The nature of the security threat was not known.