Firefighters have cordoned off parts of Central Parade in New Addington, following a build up of ice in the guttering above shops.
The fire brigade were called at 11.45am to reports of "precarious guttering and icicles overhanging the pavement," which is affecting about 30 shops.
It is understood about 250m of the street has been cordoned off, while crews work at the scene.
A fire spokesman said: "Our crews will be making sure the area is safe for members of the public as the icicles are currently overhanging and are in danger of falling down and injuring someone."
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