Police believe the head of a prestigious school and her daughter were shot dead by her husband before he took his own life, it has been reported.
The Telegraph reported the school would close on Tuesday evening and would not open again until after half term.
Emma Pattison: Key points that emerged on Tuesday
Surrey Police said Mr Pattison, a chartered accountant, had a shotgun licence and had been in contact with police about it last week.
Police said the gun was found at the scene.
The BBC reported the police believe he shot Mrs Pattison dead before killing their daughter and then himself with the same gun.
The Times reported that Mrs Pattison had contacted a close relative with concerns about her husband in the hours before the killings, and when they arrived at the house they found all three members of the family dead.
On Tuesday Surrey Police confirmed that officers have launched a homicide investigation.
The police have referred themselves to the Independent Office for Police Conduct over the case.
Detective Chief Inspector Kimball Edey, senior investigating officer on the case, said: “This is an incredibly traumatic incident and we are working around the clock to investigate and understand the exact circumstances which led to this point.
"We understand the public concern and upset, and we will clarify what we can, when we can, while respecting the right to a level of privacy for the families of those who have lost their lives.
"We are cooperating fully with the IOPC in relation to the referral we have made, and we await the outcome of its assessment of what further action may be required. Until this has been completed, we will be unable to provide further details on a number of matters."
According to reports from the Telegraph, a member of staff called 999 after hearing shots fired before the family’s bodies were discovered. It has also been reported that a rifle range on the school grounds was cordoned off on Monday.
However, police said the gun range is not part of their inquiry. It is understood that no live ammunition is kept at the range and that guns are stored in a secured armoury.
Pattison has been described as a “wonderful teacher” and a “delightful person” who had a “distinguished career”.
Police were called to the £42,000-per-year school at 1am on Sunday.
Surrey Police said it was treating the deaths as an “isolated incident” and officers were not seeking a third party in connection with the find.
Forensics officers have been seen entering the family home and a blue tent has been set up nearby.
Who was Emma Pattison?
Pattison joined Epsom College as headteacher in September. She was previously head of Croydon High School in south London and deputy head of St John’s School Leatherhead.
Pattison became the first female head of the private boarding school when she joined last August.
Until leaving five months ago, she spend six years as head at Croydon High School in Selsdon, south London, where her daughter had also been a pupil.
Watch: Colleagues pay tribute to headteacher found dead with daughter and husband
More than 850 boys and girls attend the school, which was founded in 1853, and its acting head has been listed as Paul Williams.
Mrs Pattison’s husband George was a chartered accountant who was director of a management consultancy firm called Tanglewood 2016, according to Companies House.
Tributes to Emma Pattison
Dr Alastair Wells, chair of the Board of Governors at Epsom College, said everyone at the college was in "utter shock and disbelief" at the tragedy.
He said: "Our immediate thoughts and condolences are with Emma’s family, friends and loved ones, and to the many pupils and colleagues whose lives she enriched throughout her distinguished career.
"Emma was a wonderful teacher, but most of all she was a delightful person. In time we will commemorate Emma and her family, in the appropriate way, and in line with the wishes of her family."
Croydon High girls' school, where Pattison worked until five months ago, also issued a tribute, adding: "The whole of the Croydon High community are immensely shocked and saddened by the news about our former head, Emma Pattison, her daughter Lettie who was a pupil at our Junior School and her husband George.
"Emma was a hugely respected and much loved Head of Croydon High.
"She was a warm energetic compassionate leader, dedicated teacher and generous, insightful colleague and friend."
Tributes to the popular head were posed on social media on Monday, and flowers laid near the scene.
Emma Pattison: Tributes to Lettie
Chloe Rathbown, 27, a nursery worker who used to look after Lettie, told The Times she was "utterly heartbroken".
She added: "They were such a lovely family and Lettie was perfect in every way.'
Photographer John Wildgoose, who photographed the family after Ms Pattison's headship announcement, told the newspaper: "Emma was very excited about the job and the little girl was an absolute angel.
"It was amazing how she was for the camera, it’s heartbreaking."
A past neighbour of the family told The Daily Telegraph: "You used to hear her playing in the garden, she was always asking them questions and just seemed like a happy, inquisitive little girl."
'Really big changes'
In December - four months after becoming the school's first female head teacher - Pattison told a student podcast that her family was experiencing some "really big changes" including taking new jobs, moving house and getting a new dog.
She said: "I've got a new job, my husband has got a new job, that wasn't meant to happen but it did and my daughter has started a new school so there's been a lot of change for us as a family."
She then said she wanted to "grow, learn, explore and live life to the fullest".
What has Epsom College said?
Epsom College was named Independent School of the Year 2022 at an annual awards ceremony that celebrates the very best in education and student experience in UK independent schools.
The school flew its flag at half mast on Monday.
A statement on the Epsom College website read: "It is with the deepest sadness and regret that we have to announce the news of the deaths of Emma Pattison, Head of Epsom College, her daughter Lettie, and her husband George.
"Our thoughts, condolences and sympathies are with their families at this tragic time.
"The College is working with the police in what remains an ongoing investigation. We must now focus on the welfare and wellbeing of our pupils and staff, and work to ensure that they receive all the comfort, warmth and support required from the Epsom College community.
"The news is heartbreaking and we need time and space to come together and process this loss."
Following the announcement by the police relating to the discovery of the gun the school announced it would close early.
In a letter to parents seen by the Telegraph, the acting head said they'd stayed open on Monday to come together as a community but "the details that have emerged today are incredibly distressing and we feel it is best to close the College from this evening."
Day pupils will not be expected to return until after half term, with boarding students expected to be collected between Wednesday and Friday.