The London Fire Brigade received 22 calls reporting a fire on Lord Lane in North Woolwich shortly after 2pm yesterday (December 15).
The fire destroyed three terraced houses, and around 20 people left the properties before the Brigade arrived.
There are currently no reports of any injuries.
Crews from Plaistow, East Ham, Poplar and surrounding fire stations were dispatched to the scene.
The fire was under control by 4.05pm.
The fire is believed to have been accidental and was caused by the unsafe disposal of smoking materials.
A London Fire Brigade spokesperson said: “If you smoke, it is vitally important you stub it 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.
“Firefighters recommend that you have a look at our online Home Fire Safety Checker to make sure there are no hidden hazards in your home.
“The online tool will ask you a series of questions that will help us work out the level of risk in your home, or the home of someone you care for.
“It only takes a few minutes to get tailored advice to keep yourself and loved ones safe from fire.”
