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.
More top news
A luxury penthouse in Mayfair has just broken the record for the most expensive home ever sold in the UK
Simon Harris talks to the Labour politicians hotly tipped for the Mayoral race in 2016 - but only one will admit he is standing
ITV London's Political Correspondent Simon Harris takes a look at the Labour candidates vying for the capital's top job in 2016