Detectives said today they believe millionaire businessman Christopher Foster killed his wife and teenage daughter before committing suicide.
Two bodies found in the burnt-out remains of the family's Shropshire mansion have been identified as Mr Foster and his wife Jill, officers said.
Further tests are needed to determine the identity of a third corpse discovered in the property, but it is believed to be the couple's 15-year-old daughter Kirstie, a press conference heard.
The Fosters were last seen when they attended a friend's barbecue on the evening of 25 August.
The family returned home to Osbaston House in Maesbrook afterwards and Kirstie is thought to have stayed up chatting to friends online until about 1am the next day.
West Mercia Police said the blaze at the mansion was started deliberately three hours later.
Investigators had to wait three days to get into the house due to the heat and danger of falling debris.
After entering the property on Friday, search teams discovered the bodies of Mr Foster, 50, and his 49-year-old wife.
A gun found near the two corpses was identified as a .22 rifle which was legitimately owned by Mr Foster.
Officers also found spent and unspent gun cartridges and three horses and four dogs which had been shot dead.
Detectives launched a murder inquiry after tests showed the businessman's wife had been shot in the head.
A third body - believed to be that of Kirstie - was located in the ruined mansion on Sunday night and painstakingly removed from the scene yesterday evening.
Mr Foster, 50, amassed his fortune developing insulation technology for oil rigs.
But earlier this year he was branded "bereft of the basic instincts of commercial morality" by a High Court judge, who added that Mr Foster was someone "not to be trusted".
Court documents show Mr Foster's company, Ulva Ltd, which had gone into liquidation, faced legal action from one of its suppliers for thousands of pounds and owed about £800,000 in tax.
Accountant Terence Baines, a former director of Ulva Ltd, said he feared the millionaire might have "just flipped because the pressure of it was too much for him".