Image: Jay Bartlett

A passenger has sparked a security incident at Brisbane International Airport.

The airport is now in lockdown as police investigate the concern causing major delays.

Security screening was also halted, with some passengers being re-screened.

⚠ UPDATE: The investigation with the security matter at the International Terminal is ongoing. Some passengers are being re-screened. A number of international flights will be delayed. Thank you for your patience and understanding at this time.

— Brisbane Airport ✈ (@BrisbaneAirport) March 9, 2018

There are unconfirmed reports a couple was let through security carrying a knife in their luggage.

The knife was reportedly only detected after the couple made it through security.