Immigration minister Peter Dutton has asked for an urgent review following suggestions one of two Sydney terrorism suspects may have entered Australia with false documentation.



Omar Al-Kutobi, 24, and Mohammad Kiad, 25, were allegedly about to kill or harm a member of the public with a knife as part of a terrorist attack but were arrested on Tuesday afternoon at a property in western Sydney.



Dutton says he’s been advised one of the suspects might have flown to Australia with false documentation in 2009.



He said about 50,000 people also arrived on boats around that time, under the previous Labor government, hampering intelligence agencies’ ability to check every person thoroughly.



“It is a difficult situation, particularly that period of time, for the intelligence agencies,” he told the Nine Network on Thursday.



“I’ve asked for an urgent review, in relation to all the facts in relation to this case, so that we can learn lessons.”



“Borders, at that stage, were fairly porous in Australia, with boats just coming every day.



“If the system is being overwhelmed by tens of thousands of people coming by boat, it doesn’t matter if they come by boat or plane, it’s pretty hard for the security agencies to conduct the thorough searches they need to conduct.”



The men appeared before Fairfield local court on Wednesday and didn’t apply for bail, which was formally refused.



They were due to appear at central local court on Thursday via audio visual link.