London Fire Brigade has told people in the area to "close doors and windows" amid a huge and "intense" roof fire in Deptford.
120 firefighters and 20 fire engines are dealing with the blaze on the roof of a block of flats in Creek Road.
The fire has been going since 1.03pm - four hours at the time of reporting.
Around 13 people left the building before the Brigade arrived.
There have been no reports of any injuries.
Station Commander Ian Smith, who is at the scene, has asked people in the area to "close their doors and windows" due to the smoke caused by the "intense" fire.
The cause of the fire is not known at this stage.
Ian Smith said: "This is an intense fire located in the roof of the building and fire crews are working hard in challenging conditions.
- READ MORE: Pictures from scene of Deptford roof fire
"We've increased the number of fire engines because of the need for more firefighters in breathing apparatus.
"There is a lot of smoke from the incident and we'd ask local residents to close their doors and windows."
Fire crews from Deptford and surrounding fire stations are at the scene.
A London Fire Brigade spokesperson said: "Twenty fire engines and around 120 firefighters are dealing with a fire on the roof of a block of flats on Creek Road in Deptford.
"Around 13 people left the building before the Brigade arrived.
"There have been no reports of any injuries.
"The Brigade was called at 1303.
"The cause of the fire is not known at this stage.
"Fire crews from Deptford and surrounding fire stations are at the scene."
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