Passengers who had planned on an early morning arrival into the city were left sitting in the aircraft at Kingsford Smith Airport for more than an hour as Qantas removed a group of about 10 passengers for additional security screenings before finally clearing it for take-off.

A Qantas spokesman on Monday confirmed the flight had been delayed because of a pair of scissors in carry-on bag, but would not elaborate on the circumstances.

Qantas made no comment about the flight delays on either it’s Facebook or Twitter pages, but one of the passengers affected by the delays used his Twitter account to provide running updates.

The passenger initially tweeted that the aircraft returned to gate after taxiing away, an hour after a scheduled’s departure.

Something "prohibited" in passenger’s bag was missed, he tweeted, then asked “how does this happen?”

As passengers remained on the flight, the next tweet provided an update: "Now unloading 10 people with scissors in their bag to check and reboard”.

Then, with the flight delayed by more than an hour, the passenger tweeted “now other passengers are abandoning plane as will need to fly back 30 minutes after estimated land time”.

But it was the passenger’s final tweet, which he sent just minutes before what turned out to be the eventual departure time, that finally prompted a reply from Qantas.

The passenger tweeted: “No big deal, Qantas, only meant to land in Wagga over an hour ago. Still on tarmac in Sydney.

Qantas finally replied: “Sorry Dan, safety is number one and our team will work to have you on your way ASAP. Please see the crew for further updates.”

But by the time Qantas had replied, the plane had finally cleared the gate at Kingsford Smith and taken off for the flight to Wagga.

The flight was originally due to take off from Sydney’s Kingsford Smith domestic terminal at 8.05am, but did not finally leave until 9.45am – half an hour after it should have touched down in Wagga – and eventually landed at 10.50am.

The knock-on effect meant that a return flight to Sydney, QF2222, was also delayed by almost two hours for its scheduled departure.

This flight had originally been supposed to flight of Wagga at 9.40am and land in Sydney at 10.45am, but the delay in the aircraft leaving Sydney meant it did not actually take off until 11.15am and land back at Kingsford Smith at 12,12pm.

A Qantas spokesman said these were the only two flights affected.

Passengers arriving at the airport for their on-time 1pm flight had no idea there had been any delays to earlier flights.