A quantity surveyor stabbed his wife and daughter to death before setting himself and their house on fire at the height of the first coronavirus lockdown, an inquest has heard, with the reason remaining a mystery.

Gary Walker, 57, killed 50-year-old Caroline Walker and 24-year-old Katie Walker at the family home in Stuarts Close in Hemel Hempstead on March 29 last year.

Housewife Mrs Walker, who had previously been a supervisor at Waitrose but had not worked for the last five years, suffered 39 stab wounds and kennel assistant Miss Walker 38.

Both had defensive injuries to their arms.

Detective Constable Jason Rice, of the Bedfordshire, Hertfordshire and Cambridgeshire Major Crime Unit, told Thursday’s hearing in Hatfield that, after the attacks, Mr Walker fetched two bottles of a highly flammable fluid from a garden shed.

He then returned to the house and appeared to have doused himself in the fluid and set himself alight, Mr Rice said.

Neighbours called the emergency services at around 12.30pm after seeing smoke, with firefighters finding Mr Walker dead at the bottom of the stairs, his wife’s body in the living room and that of their daughter in an upstairs bedroom.

The couple had two other children, Christopher Walker and Sarah Walker, who did not live at the family home.

Watford Observer: A forensic tent by the property in Stuarts Close Credit: SWNSA forensic tent by the property in Stuarts Close Credit: SWNS

Hertfordshire’s senior coroner, Geoffrey Sullivan, said: “The reason for these tragic events remains a mystery.

“None of the evidence we have from family, work colleagues and neighbours provides any indication or explanation of why these tragic events occurred.”

GP notes recorded that Mr Walker had a history of anxiety and had been prescribed medication in March 2020 after his recurrent issues were “triggered by the coronavirus pandemic”, Mr Sullivan said.

Mr Walker had previously seen a doctor in 2019 after becoming concerned about jury service, and in 2018 over having to give presentations at work.

But daughter Sarah visited the family home the night before the deaths and “to her mind everything seemed normal”, Mr Rice said.

Watford Observer: Photo: SWNSPhoto: SWNS

Sarah Walker lived at a different address but would visit three to four times per week and did so between around 8pm and 9pm on March 28, Mr Rice added.

“She stayed in the car and spoke to her mother and to Katie,” he said. “Mr Walker stayed inside all the time as he was watching something on the TV.”

Ms Walker said her mother mentioned that Mr Walker was “very worried about catching the virus”.

“Sarah thought these were quite normal issues under the circumstances,” Mr Rice said, adding that she was not aware of any issues at work or money worries.

Ms Walker described her father as a “quiet man”. She was not aware that he had any mental health issues, she had had a “happy childhood”, and her parents had a “normal relationship”, Mr Rice said.

Mr Rice said the pandemic had had a “major impact” on Mr Walker, who had to work from home, “which he wasn’t used to”.

“The pressure of the unknown at the time certainly had an impact on him,” he said.

He went on: “With regards to money, there’s some evidence that Mrs Walker had got herself into a degree of debt over the years, which had caused her some anxiety.

“That was approximately £20,000 and she appeared to be keeping this from Mr Walker, who wasn’t aware.”

Mr Rice said it was unclear what effect this had had on the situation.

On the day of the incident, a doorbell camera at the Walkers’ home showed a delivery arrived at around 9.30am, then about an hour later Mrs Walker visited family friends in the cul-de-sac.

Neighbour Peter Downer said he had asked Mrs Walker to buy him a speaker from eBay and she had gone to collect £70 from him to do so.

He said she “seemed her usual self” when she left his house at about 10.30am.

Around two hours later, neighbours saw smoke and called the emergency services.

Coroner Mr Sullivan recorded Mr Walker’s medical cause of death as being consistent with the effects of fire.

He recorded Mrs Walker and Katie Walker’s medical causes of death as stab wounds to the chest.

He concluded that Mr Walker died by suicide and that Mrs Walker and Katie Walker were killed unlawfully.

He described them as an “entirely normal and pleasant family”.

He extended his “sincere condolences” to the couple’s son, Christopher Walker, and to Mrs Walker’s brother, Paul Ellis, who both attended the hearing, and asked that his condolences be passed to Sarah Walker, who did not attend.

Family members who attended made no comment after the hearing.

If you have been affected by this story, there are a range of services and charities to contact. You can find out more here - www.nhs.uk/conditions/suicide