A former soldier who was convinced his ex-partner had cheated on him has been convicted of her murder.

Gary Brown stabbed Alyson Watt 42 times at her home in Paisley, Renfrewshire in June last year.

He also carried out a hammer attack on an innocent 16-year-old boy, who stayed with Miss Watt.

Brown, 55, struck after finding a text months earlier that suggested the Barnardo's charity worker may have kissed another man.

He fled after the attacks but Miss Watt, 52, was able to whisper to a neighbour the ex-squaddie was the culprit as she lay dying.

He denied murder insisting he was suffering from an "abnormality of the mind" at the time.

Brown was said to have a personality disorder.

But he now faces life in jail after jurors rejected his claims.

He had earlier pleaded guilty to the attempted murder of the boy, who now needs round-the-clock care.

Lord Summers told him: "You have been found guilty of a savage murder.

"Your stabbing was brutal and violent.

"No one who heard the evidence will ever forget it.

"Striking a defenceless young boy was also shameful and shocking.

"For these crimes, you will receive a long custodial sentence."

Brown - who showed no emotion - will return to the dock next month.

The former Scots Guard had previously served during the Falklands War.

He latterly worked as an engineer with Scottish Power.

After a failed marriage, Brown met Miss Watt on dating site Match.com around 2015.

He described her as a "beautiful looking woman" - and believed they would one day wed.

But, in March 2017, Brown discovered a text on Miss Watt's phone about a "friendly, drunken kiss" she may have had on a night out.

Jurors heard Brown became "obsessed" by the message and asked a string of people what they believed it meant.

He told the court: "It broke my heart and sent me to hell."

Miss Watt insisted she had been "100% faithful" to him.

But, for weeks, Brown let the text prey on his mind including trawling the web on how to "hack" into Miss Watt's email or social media.

He also searched: "Should I dump my girlfriend after drunken kiss".

Brown further considered going to the bar he believed Miss Watt had been that night - and asking staff had they seen a "blonde woman" with a man.

The trial heard the relationship appeared to have ended days before the killing.

But, he turned up at Miss Watt's house on June 2 after she got home from work.

He initially told her that it was not a "social call".

Brown said he then flipped when Miss Watt made a "gesture" with her hands that they were finished talking.

The thug grabbed a lock back knife from his pocket and repeatedly struck her.

Brown then discovered the boy who lived with her standing "frozen solid".

He told jurors: "I picked up a hammer and hit him three of four times."

As Miss Watt screamed for help, Brown then returned and stabbed her again.

His QC Brian McConnachie asked: "Remember stabbing her 42 times?"

Brown: "Never."

He said he believed he had only knifed her around five times.

The former soldier fled the scene and later drove to Dumfries-shire.

He claimed he planned to take his own life, but police later found him in his car.

Miss Watt's neighbour recalled how he tried coming to her aid after hearing her desperately trying to get help.

Peter Harris, 71, said: "Her hand was dragging down the window...I could see the blood running down.

"I took to my heels once I saw her. I ran straight to Alyson - into the kitchen at the back door.

"She was lying on the floor and was in a bad condition. There were wounds to her face and neck - blood was pulsing out."

"Alyson told me that it was Gary. I asked was it Gary that did it.

"She whispered 'yeah'.

"She tried to nod, but could not move her head properly."

The pensioner also found the 16-year-old boy "in a bad way".

The trial was told he suffered a severe brain injury, now needs 24-hour care and is unable to read or write.

A relative gave evidence and said the teenager is now paralysed down one side.

The woman added: "He had his whole life ahead of him and what he (Brown) has done is soul destroying."

In connection with the killing, Brown's legal team had urged jurors to convict him of the lesser charge of culpable homicide due to diminished responsibility.

It emerged after the verdict that Brown had previously been fined for a violent road rage incident.

His lawyer Chris McKenna told the court: "It is clear Mr Brown is a very troubled man resulting from his childhood and his involvement in the Falklands conflict."

Brown will be sentenced on July 6 in Edinburgh.