A woman has been arrested after three children were found dead at an address in New Malden.
Police were called at about 9.30pm last night (Tuesday, April 22) where they discovered the bodies at a five bedroom house in Thetford Road.
A 42-year-old woman remains in custody at a south London police station after officers launched an investigation.
The parents have named been locally as Gary and Tania Clarence, a South African married couple who moved to New Malden with their four children last year.
Mr Clarence is believed to have been on holiday in South Africa with the family's eldest daughter.
Police said this morning a girl aged four and two boys aged three - were pronounced dead at the scene. Their next of kin had been informed.
All three dead children are understood to have had genetic disorders.
Police placed flowers from members of the public outside the house
The 42-year-old woman was taken to hospital for treatment for minor injuries, discharged and arrested on suspicion of murder.
The oldest child who is seven or eight-years-old is in good health.
The father, Mr Clarence is understood to work in the City for Investec and Mrs Clarence is a full-time carer for their children.
The family were also understood to have a nanny and a maid at the home.
Police at the scene in Thetford Road this morning
A neighbour in Thetford Road said: "It's a quiet little street. They're a new family.
"But we know absolutely nothing.
"The house was being refurbished. They must have tripled the size of it."
Another neighbour, who asked not to be named, said: "She had her hands full. I don't know them well.
"I've bumped into her a couple of times. She was incredibly friendly.
"I'm just very sad. I was awoken last night with cars running."
The neighbour said the woman had campaigned successfully for the resurfacing of the pavement outside her house, number 29.
Ethel Winstanley, who lives opposite the couple, said she met the family last summer and congratulated them on the "transformation" of the house after its refurbishment.
"The man was called Gary, that is all I know. We went across to say 'Congratulations, you have made the street look wonderful'."
A Scotland Yard spokesman said: "A 43-year-old woman has been arrested on suspicion of murder and remains in custody. We are not looking for anyone else in connection with this incident."
VIDEOS: Neighbours describe their shock / Police officers enter and exit the house this morning
New Malden councillor Ken Smith (pictured) said he was contacted by the family some months ago with concerns about the uneven pavement outside the house.
He said: "She pointed out the pavement was a bit of a mess. The work was done within days."
The woman had been concerned about getting her children's wheelchairs into the car, he said.
Coun Smith added: "They spent a tremendous amount of money modifying the house for the children.
"They put a lift inside so the children could be moved about."
He said: "She absolutely doted on the children.
"When I spoke to the lady she was very, very concerned about the children and that they were looked after properly.
"This is a tragedy. What can one say? We don't know the full details."
A spokesperson for Bedelsford School, a school for children with physical and learning disabilities in Kingston, said: 'We are deeply saddened to hear of the deaths of three children from Kingston.
'Our thoughts and sympathy are with the family.
'We are unable to make any further comment on this as it is an ongoing police investigation.'
Kingston and Surbiton MP Edward Davey (pictured) tweeted this morning: "Awful news about the three children found dead in house in New Malden. Thoughts are with family, friends and neighbours."
Conservative prospective parliamentary candidate James Berry tweeted: "I'm sure that MPS Kingston will get to the bottom of the terrible deaths in New Malden".
Kingston borough commander Chief Superintendant Glenn Tunstall said this lunchtime: "On behalf of the Metropolitan Police Service and local Kingston officers and staff, I would like to start by offering my very sincere condolences to the family and friends affected by this tragic incident.
"This investigation is at its very earliest stages and I am in close contact with the senior investigating officer and further detail will be provided as it becomes available.
"I would like to reassure the local community that we have made an arrest and we are not looking for anyone else in relation to this incident.
"We also have additional officers patrolling in the local area and are available to deal with any concerns local residents may have.
"Specially trained detectives are currently supporting family members, who have requested that the media respect their privacy at this very difficult time."
The Homicide and Major Crime Command is investigating and an incident room has opened in Sutton under Detective Chief Inspector Diane Tudway.