Three children found dead at an address in New Malden have been confirmed as a four-year-old girl and two three-year-old boys.
All three were pronounced dead at the scene, police said.
Neighbours have suggested that the three children had been suffering from terminal genetic disorders.
The family, who are originally from South Africa, reportedly moved into the property a year ago.
A 42-year-old woman, who was taken to hospital for treatment to minor injuries, has been arrested on suspicion of murder after the discoveries.
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