Screening was paused for about 40 minutes at the Qantas domestic terminal on Monday morning after a bag with a laptop inside was not checked due to human error.

Airport security used CCTV to track down the passenger and re-screen their bag.

Hundreds of travellers were seen queuing in front of the screening gate before the passenger was found, allowing flights to take off and screening to resume about 6.50am.

While the backlog has since cleared, the security breach has led to some flight delays and cancellations.

In October, an unscreened Qantas passenger at Melbourne Airport passed through security gates, forcing others to evacuate before the individual was screened.

The airline later apologised for the disruption.