A TENEMENT building in the centre of Edinburgh is on fire amid reports of a gas explosion.

Flames and smoke were photographed by onlookers coming from between the second and third floor of a block of flats on Semple Street near Lothian Road, in the East Fountainbridge area of the capital.

Emergency services were called shortly before 5pm today. 

Scottish Fire and Rescue said around 50 firefighters were at the scene. 

It is not yet know whether anyone has been injured. 

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Calum Brown, from Dalgety Bay in Fife, works opposite the scene.

He said he felt the "glass office" shake.

The 23-year-old recruitment worker said: "I heard a bang then looked around and there was just dust rising from the ground.

"You could see smoke pouring from the chimney - I got there just before the first fire engine - you could see flames coming out of the window.

"Bricks were missing from the tenement building and had landed on the street.

"It was lucky that no-one was underneath at the time."

A van driver whose vehicle narrowly missed being struck by falling masonry told Radio Forth he could smell gas coming from the building. 

HeraldScotland:

A large area of stonework appears to have been blowing out, with images showing rubble strewn across the street below.

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The building is next to Tollcross Primary School, and the flats sit above a newsagent and sandwich shop. 

Surrounding roads have been closed and fire crews are on the scene.

In a statement, Police Scotland said: "Emergency services are in attendance following a report of an explosion and fire within a building in the Fountainbridge area around 5pm today."

HeraldScotland:

The force confirmed that Lochrin Terrace, Ponton Street, West Tollcross and access to Gardner's Crescent have been sealed off while emergency services deal with the incident.Â