Four fire engines and around 25 firefighters were called to a flat fire on Sheridan Road in Manor Park.
Part of the first floor of a mid-terraced house converted into flats was damaged by fire. Five children and two adults left the building before the Brigade arrived and were assessed on scene by London Ambulance Service crews.
A London Fire Brigade spokesperson said: “This incident is a reminder of just how important it is to have working smoke alarms in your home. Smoke alarms fitted inside the property raised the alarm, providing time for those inside to escape.
“Smoke alarms give the earliest possible warning when a fire starts. We encourage everyone to have smoke alarms fitted in every room where a fire could start, plus a heat alarm in the kitchen. It's important to test them regularly.”
The Brigade was called at 2128 and the fire was under control by 2240. Fire crews from East Ham, Stratford, Ilford and Plaistow fire stations attended the scene.