Firefighters are tackling a "massive blaze" which has taken hold of a building in Glasgow and residents are being warned to close their windows due to asbestos fears.

More than 120 firefighters are dealing with the incident on the busy shopping thoroughfare of Sauchiehall Street.

Emergency services were called to the scene at 8.18am on Thursday after a blaze took hold in the roof space of commercial premises.

Thick smoke billowed across the pedestrian precinct and streets were cordoned off as fire crews battled the blaze.

Flames could been seen in the roof of the building which houses Victoria's nightclub and has several shops at street level.

The Scottish Fire and Rescue Service (SFRS) said the occupants of nearby properties were evacuated and there were no reports of any injuries.

Assistant Chief Officer Lewis Ramsay said: "This is an extremely challenging incident but the response and professionalism of our firefighters has been outstanding.

"We would urge the occupants of surrounding buildings to remain indoors and keep their windows closed due to the suspected presence of asbestos.

"This will be a protracted incident and crews will remain on the scene as they work to prevent further fire spread and damage in this prominent city-centre location."

Firefighters were also spotted gaining entry to the nearby Pavilion Theatre.

Iain Gordon, general manager of the theatre, said: "It's getting worse, the flames are leaping out of the top now.

"Everybody is out of the area, they have all been evacuated.

"Our problem at the moment will be smoke damage because it's gone right into the side of the building.

"We are very concerned about everything. The building has been there for a long time and is a major part of Glasgow.

"When you see how quickly the fire spread to other parts of the buildings in Sauchiehall Street we just hope the flames don't jump across the lane.

"It's a lane's distance but that's not very far when it's heat and flames going across."

First Minister Nicola Sturgeon said the incident appears to be "extremely serious".

Speaking at First Minister's Questions, she said: "This is a deeply concerning incident in the city of Glasgow."

She praised the firefighters tackling the "extremely challenging" blaze and said the Scottish Government's resilience unit will remain in contact with the fire service throughout the incident.