A discarded cigarette was believed to have caused a fire at a block of maisonettes in Canning Town this week.
A man and his son managed to escape the blaze before firefighters arrived. The man suffered burns to his hands, while his son was uninjured.
Firefighters wearing breathing apparatus managed to contain the fire damage to the ground floor of the two storey maisonette in Beaconsfield Road, but the rest of the maisonette sustained smoke damage.
A London Fire Brigade spokesman said: “We believe that the fire was caused by a carelessly discarded cigarette igniting a wooden storage area in the garden.
“It’s absolutely vital you ensure your cigarette is completely out when you’ve finished smoking it.”