Eight fire engines and around 60 firefighters tackled a fire at a residential block of flats on Bakers Field in Islington.
A three-floor maisonette on the ground through second floors of the ten-storey building was alight. Half of the ground and first floors and part of the second floor were damaged by fire. Around 35 residents were taken to a nearby rest centre. There are no reports of any injuries.
The Brigade's 999 Control Officers gave vital Fire Survival Guidance (FSG) to those inside the building on how to stay safe before firefighters arrived.
A London Fire Brigade spokesperson said: "The Brigade's FSG app enables Control Officers to manage incidents like this one, where multiple people within a building have contacted the Brigade and require at times lifesaving advice on staying safe.
"The app also allows information to be quickly and accurately exchanged between Control Officers and firefighters at the scene so safety advice can reflect any changes as the incident develops."
Control Officers received around eight calls to this fire, with the first call received at 0414. Control Officers mobilised crews from Kentish Town, Holloway, Islington and surrounding fire stations to the scene. The fire was under control by 0539.
The cause of the fire is under investigation.