An 18-year-old mother has died after she was found on fire in a street in south-west London.
Emergency services were called at 1.10am on Sunday morning to reports of a burning woman on the level crossing near a Tesco branch at West Barnes Lane in New Malden.
They managed to extinguish the fire but the woman, believed to be around 18 years old, was pronounced dead at the scene.
The Met Police said her death was being treated as unexplained but early indications suggested it was not suspicious.
The cause of the fire and circumstances of the death are being investigated by officers from the Homicide and Serious Crime Command and the London Fire Brigade, a police spokesman said.
Officers have confirmed the teenager had a young son, who was being looked after by relatives when she died and remains in their care.
Layla Hamid, 20, who was house-sitting in a home adjacent to the scene, said she heard four screams but thought it sounded more like a fox than a person in pain.
She told Sky News: "At about 1am, I heard what sounded like a scream. It was the strangest noise. I thought it must be an animal but I now know it was someone screaming.
"She was not screaming for help and it was not screaming continuously. There were four screams in total. One came from the house then progressed down the road.
"When I heard it was a girl on fire I was shocked.
"I thought something is not not right there. If something had blown up in the house I would have heard that.
"An hour after I heard the scream the police were already at my door. And then when I woke up there was a white tent there."
She said she did not know the occupant who lives at the house where the woman ran from but had not seen anyone come and go from it regularly.
A spokeswoman for the London Fire Brigade said the woman had suffered burns on every part of her body.
Nearby Burlington Road and neighbouring streets were sealed off.
Officers believe they know the identity of the deceased and have informed next of kin. A post-mortem examination will be arranged in due course, and no formal identification has taken place.
Scotland Yard said it believed the fire started in a house in Linkway.
Police issued an appeal for witnesses, saying in particular they needed to speak to three members of the public who assisted in trying to save the woman's life by trying to extinguish the flames.
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