FIREFIGHTERS are responding to a gas explosion on Mort Street in the city.

Update to come.

The gas explosion is believed to have occured in the McDonalds restaurant.

Firefighters are still investigating and attempting to shut off the gas.

The seven floor appartment block above the restaurant has also been evacuated.

ACT Fire & Rescue has three pumpers, a commander and the hazardous materials unit on scene.

The ACT Ambulance Service is also in attendence.

One man has been taken to the Canberra Hospital in a serious condition with burns to his body.

No one else is being treated at this stage.

Firefighters are ventilating the McDonalds restuarant after locating the cause of the explosion.

Further monitoring is also underway to ensure there are no further pockets of gas.

Crews have isolated the sprinkler system and residents have been allowed to return to the apartment building.

ActewAGL are also on scene along with ACT Policing.

ACT Fire & Rescue has also called in the Breathing Apparatus Van.

Crews will remain on scene for some time.

This in from ACT Policing:

ACT Policing attended McDonalds restaurant in Braddon this evening (Sunday 13 September) following a small gas explosion.

About 9pm, a 41-year-old man from Giralang entered the restaurant and ignited a 9kg gas bottle which he had brought with him. The man sustained possible life threatening injuries. He was treated at the scene by ACT Ambulance and conveyed to the Canberra Hospital.

No other patrons or staff were injured in the explosion.

ACT Policing and ACT Fire and Rescue evacuated the occupants of the restaurant and the floors immediately above in James Court as a precaution.

Cooyong Street was closed between Mort Street and Northbourne Ave while the cause of the explosion was determined.

Investigations are ongoing but police do not believe there is any further risk to the community.

Police are urging anyone who witnessed the incident or has information that could assist police to contact Crime Stoppers on 1800333000 or online via act.crimestoppers.com.au. Information can be provided anonymously.

[Photo via ACT Policing]