Officers say they were made aware of the incident near Carlton Place and Portland Street in the city at around 12pm on Saturday, January 27.
We previously reported that the Scottish Fire and Rescue Service was pictured on the scene along with ambulance and police crews.
Following the fire, cops revealed that there were no reported injuries.
However, they have said the blaze is being treated as deliberate.
An investigation into the incident is underway.
A spokesperson for the Scottish Fire and Rescue Service said: “Around 12pm on Saturday, January 27, we were made aware of a fire at a property on Carlton Place, Glasgow.
“Emergency services attend, there were no reports of injuries and the fire was extinguished.
“It is being treated as wilful and enquiries are ongoing to establish the full circumstances.”
