Over 400 people are reportedly being stopped every day at national airports as counter-terrorism authorities step up efforts to prevent potential jihadists from leaving Australia.

Teams from the Border Force Counter-Terrorism Unit have conducted almost 76,000 “real-time assessments” of prospective travellers since August last year, Fairfax reports .

The examinations involve asking “suspicious” individuals a series of questions to assess whether they represent a national security risk, although it is not known how many of these individuals have been apprehended further.

Individuals have reportedly been removed from aircraft, had their luggage searched and technology probed. It is believed a number of travellers have been caught with “extremist material” on their phones.

The revelations come after two teenagers were sent home from Sydney airport earlier this month with their mother, after being detained by counter-terrorism officials.

The 15-year-old and 16-year-old brothers had reportedly booked tickets to fly to the Middle East.

Immigration Minister Peter Dutton said the intercept had kept their family together and likely prevented the boys from entering “potentially a very dangerous situation.”

“It is yet another reminder of the need for parents to remain vigilant against this type of threat,” he said.

Last week it was reported that Melbourne teenager Jake Bilardi, a Islamic convert who joined ISIL, reportedly died while carrying out a suicide bombing in Iraq which killed dozens.

Police then found “explosive devices” at the 18-year-old’s home.