Assistant Commissioner Andy Pennick, speaking from the incident said: "Fifteen fire engines and around 100 firefighters were called to a fire at a terraced property of three floors on Cazenove Road in Stamford Hill.
"Additional resources were deployed to the scene as the fire involved the roof. Pockets of fire were also tackled on other floors of the building. The fire is now under control, and crews will be carrying out further firefighting operations into the evening.
"The Brigade took the first of over 40 calls at 1614 and Control Officers mobilised crews from Stoke Newington, Islington, Walthamstow and surrounding fire stations to the scene. Three of the Brigade's 32-metre turntable ladders were also deployed. Three people were treated at the scene for smoke inhalation, with two taken to hospital for further treatment. Crews also carried out salvage operations in the impacted and neighbouring properties.
"Our Community Engagement team are working with the local authority and community leaders to support local residents affected.
"People are advised to still avoid the area at this time whilst firefighters remain on scene.
"At this stage, we do not believe that the fire was started deliberately, however, investigations are ongoing by our Fire Investigation Team to determine the cause of the fire."
Moishe Friedlander, liaison for local police and Hatzola, said: "Hatzola was called at 1614 in relation to a fire at Cazenove Road and three paramedics, two ambulances, two fast response units and 10 members responded. I would like to thank all emergency services who responded and worked so well together."