Property developer Roger Goswell was known to his neighbours as a roguish businessman with a taste for fast cars.

He and his 63-year-old wife Sue, a "bubbly, lovely lady" had been married for 46 years and had three children.

But on Sunday night Mr Goswell stabbed his wife with a kitchen knife and hit her over the head with a mallet.

As she lay dead on the living-room floor, he pinned a note on the front door of their £700,000 house in West Chiltington Common, near Storrington, which read: "Police entry only".

Leaving his Maserati sports car in the garage, the 66-year-old killed himself by driving the couple's Smart car into a tree.

Police are now trying to find out what sparked the tragic events that took place only days after Mr Goswell was released from a psychiatric ward.

The deaths are being treated as murder and suicide.

While it could be several months before the full truth is made public, questions have been raised about the way Mr Goswell's condition was handled by mental health authorities.

His children said both their parents were "let down by the system".

Mr Goswell had been treated at two hospitals for mental health problems in the month before the deaths. Mrs Goswell reportedly told neighbours she did not feel "safe or comfortable" about him returning home.

Their children, Sarah, Joseph, Rebecca and son-in-law Alex, issued a statement saying: "We would like to take this opportunity to pay tribute to our beloved mother. She was a wonderful parent, wife and friend to many. Our father was a tortured soul and unfortunately in the end we feel they were both let down by the system."

Detective Chief Inspector Adam Hibbert, who is leading the investigation, held a press conference at Littlehampton police station yesterday: He said: "I am aware questions are being raised about how various agencies responded to concerns in the hours, days and weeks before this tragic series of events.

"I am unable to deal with these issues today, but the full facts of my investigation will be presented to the coroner in due course."

Sussex Partnership NHS Trust confirmed Mr Goswell had been released from a psychiatric hospital days before the deaths.

In late November, he was admitted to the Harold Kidd Unit in Chichester and then transferred to the private Priory Hospital in Hove, before being released the week before his death.

A spokesman for the trust said: "We are doing all we can to work with the coroner's office and the police on this issue and send our condolences to the family.

"Mr Goswell passed through our services, but we were not responsible for looking after him afterwards."

The spokesman refused to be drawn on whether a review or inquiry would be launched, but said they would see what came out of the coroner's investigation.

The Priory Hospital refused to comment on the deaths.

Outside the couple's £700,000 home in Silverwood, West Chiltington Common, the couple's two daughters, Sarah and Rebecca, and son Joseph left a bouquet of flowers for their mother.

The card read: "To a loving and devoted mother, love from all your children, we love you mum x."

Another tribute read: "To Sue, loved by all, Paul and Nancy x."

Mr and Mrs Goswell were childhood sweethearts who ran pubs including the Squire and Horse at Bury and the Stonemasons Arms in Petworth.

He went into property development, while she worked as a hairdresser.

Mr Goswell was a keen golfer and was a member of the Avisford Park club in Walberton, near Arundel, and Arundel Cricket Club's golf society.

Fellow cricket club member Nick O'Brien said: "Roger had been a member of our golf society for some time. I've known him for 20 years or so. This is a total, total shock. Susan was a bubbly lady, absolutely lovely."

No flowers were left at the tree on Monkmead Lane, just before Harborough Hill, into which Mr Goswell's car smashed.

The crash happened on Sunday at 8.45pm.

Mr Goswell had driven into a tree half a mile from his home in misty conditions.

He was not wearing a seatbelt. He was taken to Worthing Hospital, but died just before 1am on Christmas eve.

Police traced his address using the car number plate and called at his house.

When they arrived they found the front door unlocked and the note pinned to it.

Inside they found Mrs Goswell's body sitting on the living room floor.

She had been stabbed at least three times and struck on the head with a blunt instrument.

She was drenched in blood but there was no other sign of a struggle in the house. Detectives removed a kitchen knife and a wooden-handled rubber mallet from the home for analysis.

A post-mortem examination was carried out on the bodies on Christmas eve and boxing day.

Officers are waiting for the results of tests which will reveal whether there was any trace of alcohol or other substances in their blood.

Neighbours did not hear anything on the night of the deaths.

Police are trying to establish the exact time when Mrs Godwell died, but said she had been seen alive and well on Sunday afternoon.

Neighbours told The Argus the couple were on the verge of divorcing and had recently put their £700,000 house up for sale.

Dianna Dennis, who lives in Silverwood, said Mrs Godwell had confided in her that they were having arguments, mainly about money, and that their marriage was on the rocks.

She said: "Sue came to my house about three weeks ago. She said she was very concerned about Roger and said they had been arguing a lot recently and not getting on very well. She said they were going to split up."

The tragedy again draws the spotlight on whether people with mental health problems receive appropriate care.

In June, Clare Moorhouse, a 42-year-old landscape gardener, hanged herself after being released unsupervised from Millview Hospital.

Poor note-keeping, a lack of communication between the hospital and the dead woman's family, use of "inappropriate"

medication and a failure to properly assess her mental state were all criticised by Brighton and Hove coroner Veronica Hamilton-Deeley.

In February, retired butcher Dudley Nightingale attacked his wife of 40 years with a kitchen knife at their home in Ferring before stabbing himself to death.

An inquest into his death was told Mr Nightingale suffered from depression, but had told a Sussex Partnership psychiatrist he had stopped taking his medication.

In January, Edward Edrich, 59, shot his wife Claire dead at their four-bedroom home in Lowfield Heath, near Crawley.

He was suffering from depression and detained under the Mental Health Act after admitting manslaughter at Lewes Crown Court.