Firefighters have issued a smoking safety warning after a house fire on Woodcroft Road in Stanmore.
Part of the ground floor of a semi-detached house was damaged by fire. There were no reports of any injuries.
A gas cylinder in the garden was cooled to an ambient temperature as a precaution, as some cylinders can explode when exposed to heat.
The fire is believed to have been accidental and caused by the unsafe disposal of a cigarette.
A London Fire Brigade spokesperson said: "If you smoke it's vitally important you stub cigarettes right out, preferably in an ashtray.
"Always ensure your cigarette is completely out when you’ve finished smoking it. If you don’t, you risk causing a fire which could not only destroy your home, but also cost you your life."
The Brigade was called at 0011 and the fire was under control by 0152. Four fire engines and around 25 firefighters from Stanmore, Harrow and Northolt fire stations attended the scene.
Smoking safety top tips