Police have appealed for witnesses and urged the "criminal fraternity" to help find the killers of Michael Samwell who was run over by his own car.
Mr Samwell, 35, died after going to confront intruders who broke into his home as he slept upstairs with his wife Jessica at 3am on Sunday.
The former Royal Navy officer was found seriously injured in a parking area at the rear of his house in the Chorlton area of Manchester and died around an hour later in hospital.
Police believe he was run over at least once as he tried to stop the intruders from making off with his black Audi S3 sports coupe.
The car was later found abandoned three miles away in the Ladybarn area of the city and was extensively damaged.
Mr Samwell's killers remain on the run and a manhunt is under way.
Detective Superintendent Jon Chadwick, of Greater Manchester Police, said: "This is the murder of an innocent man who has merely sought to protect his property from criminals.
"We will not stop until we have found the person responsible for this dreadful crime."
He added: "It is one of those things where you would expect the criminal fraternity to help us out with. It's more than criminal."
Mr Chadwick said Mr Samwell's wife had been left "devastated" and was being comforted by her family.
According to LinkedIn, Mr Samwell trained as a naval officer at Britannia Royal Naval College in Devon and spent around a decade in the senior service before leaving in 2014.
The page says the University of Leeds graduate worked in several roles, including on board a nuclear attack submarine as a weapons officer.
Since leaving the Royal Navy he had worked as a programme manager for engineering firm Atkins in Warrington, Cheshire.
An Atkins spokesman said: "This is a tragic event and our thoughts go out to Mike's family, friends and colleagues. We will support the family in any way we can."
:: Anyone with information is asked to contact police on 0161 856 9908 or 101.