A wealthy antiques dealer from Raynes Park who strangled his daughter has changed his plea to guilty midway through his trial.

Robert Peters was standing trial at the Old Bailey where he was accused of murdering his seven-year-old daughter Sophia.

The accusation was that the 56-year-old dad had throttled her with a dressing gown cord while alone with her at his £1 million family home.

Afterwards, he called 999 to report what he had done and the child was rushed to St George’s Hospital in Tooting.

Sophia was placed on a life-support machine but died the following day while her dad was charged with murder.

The killing came just over a month after depressed and suicidal Peters was found not to be a risk by a child protection team.

He had admitted manslaughter but denied murder, saying he was depressed and hearing voices at the time.

But on the third day of his trial today (April 25), Peters dramatically changed his plea and admitted murdering Sophia.

In the months before the killing, Peters searched the internet for "serial killers", "treatment of child killers in prison" and "premeditated murder".

He chose his opportunity to kill her before she was due to return to her £5,000-a-term boarding school after the half-term break.

Peters waited until his wife had gone out before he woke Sophia up in bed by tying a cord around her neck and throttling her for up to half an hour.

She asked him what he was doing and Peters said "sorry", but carried on as she struggled, the court heard.

When officers arrived at his Blenheim Road home, Peters calmly told them: "She's upstairs. I've strangled her."

Sophia was found curled up in bed wearing a nightie and knickers with a black fleece dressing gown cord wrapped and knotted tightly round her neck.

She had a weak pulse and was rushed to hospital, joined soon after by her mother, who was escorted there by police.

Sophia was treated in intensive care but died from brain damage the next day, on November 4 last year.

Following his arrest, Peters admitted not being a "good father" and said he had been suffering a breakdown.

He said he had been thinking of killing his wife and family for several weeks so they could be "spared the pain and upset when he became bankrupt".

Detective Inspector Helen Rance, of Scotland Yard, said: "Sophia was an innocent seven-year-old girl, much loved by her mother, brother and friends. She was tragically murdered by the hands of her own father in the most frightening way.

"Sophia had her whole life ahead of her, which was taken away so cruelly in an act of pure selfishness. Robert Peters has shown no remorse for the murder, and initially maintained a defence of diminished responsibility. However, due to the strong evidence against him, he has changed his plea to guilty.

"This was a particularly traumatic case to deal with for all concerned, and I hope that this conviction brings a degree of closure to Sophia's family."