Four people were arrested in the raids which were carried out across Sydney yesterday afternoon.
One of four men arrested over a suspected terror plot to bring down a plane has been released without charge in Australia.
Security at Brisbane Airport was visibly beefed up on Sunday, with travellers asked to arrive early and pack light.
"What you are seeing at the moment is making sure that there is extra vigilance, to make sure that we aren't cutting any corners in our security, to make sure that we are absolutely focused on our security", Colvin said.
Turnbull said advice from Australian security and intelligence agencies had led to increased security measures at Sydney airport on Thursday, while the country's other domestic and global airports were affected from Saturday. REUTERS/David Gray Australian Federal Police and NSW Police officers work in the Surry Hills suburb of Sydney, Australia on Saturday, July 29, 2017.
"Travellers should be prepared for additional scrutiny at screening points, and while it is important that Australians are aware of the increased threat, be assured we have the finest security and intelligence services in the world and they are working, as is my government, and all our governments around Australia, night and day to keep Australians safe", he said.
Passengers at major Australian airports, including Sydney, experienced longer-than-usual queues during the busy Monday morning travel period.
Inter-state travellers are subjected to far less scrutiny than those travelling overseas with no formal identification checks required for domestic trips.
Australia has been on heightened alert since 2014 for attacks by home-grown militants returning from fighting in the Middle East, or their supporters, but has suffered few domestic attacks.
Police previously said the men planned an attack on targets which included the AFP headquarters in Sydney, along with civilian targets.