Firefighters responded to a structure fire at 4.21am on Barkers Road, Hawthorn, after triple zero (000) callers reported a unit fire.
Fire Rescue Victoria (FRV) firefighters arrived on scene within seven minutes to find a unit, about 30m by 10m, fully involved in fire and escalated the response to a third alarm due to crews having difficulty gaining access to commence operations.
Crews wore breathing apparatus to battle the blaze, which was deemed under control at 5.11am.
At the peak of the response, 60 firefighters and 19 fire trucks were on the scene, including two aerial fire trucks.
A Community Advice warning was also issued for smoke in the area.
The cause of the fire is unknown at this stage.
Victoria Police and Ambulance Victoria are on scene assisting FRV operations, who remain on the scene at 6.30am.
Roads in the area remain closed or restricted due to firefighting operations.
