ACT Fire Brigade on scene at West Block offices, Queen Victoria Terrace, Parkes at a small electrical fire.
Fire has been extinguished.
Approx 250 people evacuated as a precaution as crews clear heavy smoke logging.
Three fire pumpers, the Bronto Skylift Hydraulic Platform, the specialist Breathing Apparatus Unit and Hazardous Materials van on scene.
Crews alerted following Automatic Fire Alarm at 2.29pm.
Crews conducting ventilation and air monitoring before allowing workers to return to building at approx 3.30pm.