The New South Wales top cop believes charges will be laid against the three men held over an alleged terror plot to blow up a plane.
Police Commissioner Mick Fuller says the evidence against three men, who were arrested in raids across Sydney, is "very strong".
"We have secured a number of search warrants," he said on Thursday.
"We are forensically going through these premises to make sure every piece of evidence is identified".
One man has been released without charge, with police granted special powers to hold the other three until Sunday night.