Four fire engines and around 25 firefighters were called to a fire at a block of flats on Hoey Court in Poplar.
Half of a wooden balcony on the fifth floor was destroyed by the fire and two pet parrots sadly died.
Fire investigators believe the fire was accidental and the most likely cause is due to the unsafe disposal of smoking materials.
Sub Officer Nick Wilson was at the scene, he said: "Crews worked extremely hard to contain the fire and successfully stopped the fire spreading to the neighbouring balcony on the floor above.
“If you're a smoker, it’s absolutely vital you 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 2013 and the incident was over by 2118. Crews from Poplar, Milwall, Stratford and Shadwell fire stations were in attendance.