Canberra Airport has been evacuated and planes have been grounded after a gunman fired shots near the check-in security screening area of the terminal.
ACT police has taken the man into custody and while a firearm had been recovered.
Police say CCTV footage shows the person in custody was believed to have been the only person responsible for the incident.
There have been no reports of injuries.
Three bullet holes can be seen in the glass windows of the departures terminal.
ABC reporter, Lily Thomson heard the shots and realised something was wrong when people started screaming "run".
She says she saw this grandma with a baby and the fear in her face and says she knew it was something serious.
Thomson says they all ran and she stayed with that grandma and her baby and hid behind an information desk.
The reporter says they stayed there for a couple of minutes until security told them to evacuate out to the car park.
She says everyone was hiding behind chairs and people were running.
Thompson adds it was terrifying, they didn't know what was going on and the look on people's faces was quite terrifying.
The airport is still locked down and about five planes remain on the tarmac as Australian Federal Police continue to sweep the entire terminal and interview witnesses.
A passenger in one of the planes is ABC News presenter Dan Bourchier who says it is still unclear as to when passengers would be able to disembark.
Source: ABC
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