Thick smoke and flames ripped through the four-storey building in Crow Road, Partick, yesterday morning.
As reported in late editions of yesterday's Evening Times, six people, including two children, were taken to hospital after the fire broke out around 2.20am.
Firefighters, using thermal imaging cameras, yesterday began the salvage operation in the property.
The cause of the blaze remains unknown, but the Incident Research and Investigation Section of Strathclyde Fire and Rescue is investigating.
Around 20 people were evacuated from their homes in two blocks, in Crow Road block and Fairlie Park Drive, as firefighters battled the blaze.
A 49-year-old woman was taken to the Southern General Hospital, with severe smoke inhalation and "significant" burns.
She was later transferred to Glasgow Royal Infirmary, where she was described as "serious".
Two children were taken to the city's Yorkhill Children's Hospital as a precaution and have since been discharged.
Another woman and two men were taken to the city's Western Infirmary where they were also treated for smoke inhalation. All three adults were discharged from hospital yesterday.
Group Commander Richard Duncan said crews from Yorkhill and Cowcaddens stations were presented with a "well-developed" fire.
He added: "Owing to the intensity of the fire and number of persons involved, the Incident Commander requested further resources from Springburn, Knightswood and Milngavie Fire Stations, with a total of 35 firefighters at the scene at the height of the blaze."
Residents were allowed to return home for 20 minutes to collect belongings.
Many had spent the early hours of yesterday morning in Patrick Burgh Halls or with family and friends.
Part of Crow Road, near Dumbarton Road, was sealed off as fire investigators examined the property.
Meanwhile, two people were rescued and taken to hospital and 14 evacuated after a fire in a ground-floor flat of a three-storey block of flats in Maryhill, also in the early hours on Monday morning.
The incident occurred at around 12.30am – just two hours before the blaze in Partick.