Travellers stranded after Cairns Airport evacuation

A full evacuation of Cairns Airport was sparked after a female passenger accidentally accessed an off-limits area.

Cairns Airport operations manager Kate McCeery-Carr told the Cairns Post an alarm was activated after the woman went the wrong way through an exit.

"We have spoken to the lady and it is believed she forgot something and left the plane to run back to get it," Ms McCeery-Carr said.

"She thought because she had been screened it was all ok.

"She is very apologetic, but we had to do a full evacuation."

Passengers at the airport told 9news.com.au there were "federal police everywhere" as passengers were ordered out of the terminal. 

At least five flights were delayed as passengers battled large lines to be re-screened through security.

Airport and retail staff inside the terminal were also evacuated during the breach.

The delays are clearing as airport operations return to normal.