The Scottish Fire and Rescue Service was alerted at 6.18am on Tuesday, August 24 to reports of a building on fire at George IV Bridge.
Operations Control mobilised nine appliances and two height vehicles to the area where the fire was found to be affecting a number of properties. A further three appliances were mobilised.
Crews remain on the scene and are expected to do so for some time as they work to make the area safe.
Scottish Fire and Rescue Service’s Deputy Assistant Chief Officer David Farries is the Incident Commander. He said: “This is undoubtedly a complex and challenging incident.
“I would like to thank our crews as they work to extinguish the fire. I would also like to thank our emergency services colleagues and local authority partners.
“We will remain in attendance for a considerable time yet as we work to contain the fire.”
DACO Farries continued: “We continue to ask people living nearby to keep windows and doors closed due to smoke.
“Road closures remain in place and we advise people to avoid the area and to allow access for emergency service vehicles.”