Part of the basement and ground floor were destroyed in the blaze.
A woman aged 46 was found by emergency services inside the property with stab wounds. Despite the efforts of paramedics, she was declared dead at the scene.
A 44-year-old man was arrested at the address on suspicion of murder, the Metropolitan Police said.
He was taken to hospital with slash wounds where he currently remains. His condition is not life-changing or life-threatening.
Two children aged seven and nine have also been taken to hospital as a precaution but are not believed to have been inside the property at the time of the explosion.
A friend of the family told the Standard they found out their neighbour had been killed on the school run.
Through tears, the man who lives nearby to the family said: “We know them well. Our kids are in the same class. The school is on the corner. We are all here because of the school.
“They have two little boys. The kids were out at a sleepover. We know the family from birthday parties, everything.
“Our kids have been in the same class for a couple of years. They were just a lovely family. It’s just unexpected.”
Describing the explosion, he added: “It was confusing. We thought it was in our house. I couldn’t place it.
“I found out what happened on the school run.”
Police and the fire service at the scene
Twins Sarah Ayob and Sumaiyah Ayab said their beds shook five five doors down from the explosion.
Sumaiyah said: “I thought a car had smashed into the side of the house. A neighbour came out and was screaming.”
Sarah added: “Even our neighbour on the other side heard it as well. It was really loud. I have never heard anything like it. There was glass everywhere.”
One resident spoke of her shock and said a man and a woman lived in the house with young kids.
“Everyone around here has kids at the primary school. People will be very shocked to see this,” they said.
“We came out when we heard the explosion. The fire engines were here very quickly. We couldn’t really do anything to help.”
A neighbour who lives just metres from the property told the Standard his house shook as the explosion happened.
He described how he heard what sounded like a “really loud clap of thunder”.
The resident left his home after a few minutes to see what had happened.He said: “There wasn’t a fire or anything. Everyone was just in shock.”
The front of what looks like the living room of a Victorian terraced property appears to have been cracked by the explosion.
The wood had become visible and the window has been completely destroyed.
Emergency services at the scene
Lily Shanagher/PA Wire
Glass and debris remained spread across the road around 10 metres from the exploded home
The incident was brought under control by 5.42am by the Brigade but a cordon remains in place.
A large police cordon was in place with several fire engines still at the scene at 8am.
A resident on Dumont Road said he heard a crash “like somebody dropped a massive glass cabinet from a crane”.
The man, who did not want to be named, added: “I looked out and saw panes of glass on the floor. You could tell it wasn’t a car window.
“Eventually I noticed the beam on the bay window was missing and could see some mild smoke coming out of the back.
“People starting arriving and saying to phone the police.
“There was a guy rushing around, very distraught. He went round the back.”
A 76-year-old neighbour said: “I was asleep upstairs and heard a sudden bang then I saw from the curtain all the glass all on the floor.
“I was worried. Everybody on the street came out in their pyjamas.”
Another neighbour said: “I’m pretty sure it was two bangs I heard. There was lots of glass shattering.
“I knew it wasn’t a car crashing because it sounded like lots of glasses had been smashed on the floor.”
Emergency services near to the scene of a suspected gas explosion
Lily Shanagher/PA Wire
Station Commander Darren McTernan, who was at the scene, said earlier: “Motorists and pedestrians are advised to avoid the area for most of this morning while investigations into the cause of this incident are carried out.”
The LFB was first called at 4.52am and crews from Stoke Newington, Holloway, Islington and Homerton fire stations to the scene.
The cause of the explosion is under investigation by the Brigade and the Met Police.
Forensics officers could be seen at the back of the property as the murder investigation was launched.
London Ambulance Service said: “We were called today at 4.46am to reports of an incident in Dumont Road, Stoke Newington, N16.
“We sent resources to the scene including ambulance crews, a paramedic in a response car, an advanced paramedic practitioner, members of our hazardous area response team (HART) and London’s air ambulance.
“Sadly, despite our best efforts, a woman was pronounced dead at the scene. A man was taken to a London major trauma centre. Two children were taken to hospital for a precautionary assessment.”
Anyone with information about the incident can call police on 101, quoting CAD 926/17June, independent charity Crimestoppers via 0800 555 111.
