Scaffolding surrounding the building, as well as the ground floor and the roof are alight.
Forty fire engines and around 225 firefighters are battling a blaze at a block of flats in Dagenham, east London.
The London Fire Brigade (LFB) said it was called at 2.44am on Monday with crews from Dagenham, Ilford, Romford, Barking and surrounding fire stations at the scene.
The brigade said parts of the scaffolding surrounding the building, as well as the ground floor and the roof, were alight.
Four people had to receive medical treatment from the London Ambulance Service.
Two people were taken to hospital because of their injuries.
The cause of the fire has not been established.
Video footage showed thick black smoke rising above the building. The fire brigade used a drone to see where the flames were most intense.
Station commander Alan Bendell is at the scene and said: “The fire is producing heavy smoke and we’re advising local residents to keep windows and doors closed.
“Two of the brigade’s 32-metre turntable ladders are being used at the scene as aerial water towers to assist with tackling the fire from height.”
An ambulance service spokesperson said: “We treated four patients at the scene and took two of them to a hospital.”
For all the latest updates, follow our live blog below. Are you at the scene? Did you see what happened, email rebecca.perring@reachplc.com.
Firefighters are tackling a huge blaze in Dagenham
The fire brigade tackling the blaze
Home Secretary Yvette Cooper posted on X: “My thoughts are with all those affected by the major fire incident in Dagenham. I thank London Fire Brigade & all emergency services on the ground for their bravery and swift response.
“I and @ukhomeoffice Ministers are receiving updates on the incident from operational partners.”
Rest centre set up near the scene
A rest centre has been set up at Beacontree Heath leisure centre, Patrick Goulbourne, incident commander and an Assistant Commissioner at the London Fire Brigade has confirmed.
He said: “Officers with our partners are stationed there to help residents.”
Cladding was being replaced at block of flats
The “non-compliant” cladding was being removed before the fire on Monday.
A company involved in the work said that the removal was focused mainly on the fifth and sixth floors.
It’s not yet known what caused the fire.
More pictures from the scene of the fire
Pictures show the fire at its peak and the damaged caused after the flames were quelled.
Police at the scene
The aftermath of the fire
Full statement from London Fire Brigade Commissioner
London Fire Commissioner Andy Roe said: “We were called to the incident at 0244 this morning.
“The first crew arrived within five minutes and the second crew arrived within six minutes. An aerial appliance also arrived in under six minutes. To allow us to focus our resources on the incident, we have declared a major incident.
“The building has a number of fire safety issues known to London Fire Brigade. A full simultaneous evacuation of the building was immediately carried out and a significant search and rescue operation is underway.
“The Brigade’s Control Officers have taken 16 calls to the fire, including successfully giving vital fire survival guidance to a number of people using our Fire Survival Guidance App, which allows information to be exchanged between Control and the incident ground in a timely, accurate and consistent manner.
“We are also using new equipment such as drones and our 64-metre turntable ladders and 32-metre turntable ladders to provide incident commanders with a vantage point for assessing the scene. They are also being used as water towers to deliver water on to the fire from above.
“The Brigade has stood up full strategic arrangements to deal with the incident and a rest centre has been set up at Beacontree Health and Leisure Centre. LFB officers are stationed at the rest centre to support residents.”
Fire Brigade Commissioner declares ‘major incident’
London Fire Brigade Commissioner Andy Roe has declared a “major incident.”
40 fire engines and 225 firefighters responded to the fire
London Fire Bridage deployed a lot of resources to tackle the blaze.
Video footage shows the extent of the fire
Video footage shared on social media shows the fire.
Where is the incident happening?
Locals told to keep windows and doors closed
Station Commander Alan Bendell, who is at the scene of the fire, said: “The fire is producing heavy smoke and we’re advising local residents to keep windows and doors closed.
“Two of the Brigade’s 32-metre turntable ladders are being used at the scene as aerial water towers to assist with tackling the fire from height.
“Freshwater Road is closed to traffic, so please avoid the area where possible.”