Image copyright West Midlands Police Image caption Tracey Wilkinson died at the family home in Stourbridge and her teenage son Pierce died in hospital

A "manipulative" homeless man who turned on a family who befriended him has admitted the "frenzied" murder of the mother and her 13-year-old son.

Tracey and Pierce Wilkinson were stabbed to death at their home in Stourbridge, West Midlands in March.

The boy's father, Peter, was seriously injured in the attack but survived.

Aaron Barley, 24, of no fixed address, admitted the killings at Birmingham Crown Court on what would have been the first day of his trial.

He previously admitted the attempted murder of Mr Wilkinson.

The family first met Barley after Mrs Wilkinson decided "off-the-cuff" to help him when she saw him trying to keep warm in a cardboard box while she was out shopping.

She helped him find accommodation and arranged daily meals for him, while her husband went on to employ him as a labourer in April last year.

He left the company on "amicable terms" last September after he began to take drugs.

Image copyright West Midlands Police Image caption Aaron Barley admitted the two murders on what would have been the first day of his trial

Prosecutor Karim Khalil QC told the court Mr Wilkinson was "naturally intent" on trying to continue to support Barley and his work colleagues "spent a huge amount of time and effort trying to find ways to support the defendant".

But despite this he went on to attack the family just months later.

'Acting like a ninja'

Mr Khalil said Barley killed Mrs Wilkinson in her bed and attacked Pierce in his room while Mr Wilkinson was out walking the dog on the morning of 30 March.

He had hidden in the garden shed overnight after failing to gain entry to the home he once shared with the family.

CCTV played to the court showed him emerging from the shed with a hammer as Mr Wilkinson returned home.

Brandishing a knife over his head, he shouted "Die you bastard" as he stabbed Mr Wilkinson a total of six times - twice in the face, twice in the abdomen and twice in the back, the court heard.

Barley, described as a "compulsive liar and manipulator" with 21 previous convictions, wore a balaclava and was clad entirely in black, even covering his yellow trainers in black socks.

Mr Khalil said Mr Wilkinson described the defendant as "acting like a ninja".

"He realised immediately who his attacker was", he said.

Media playback is unsupported on your device Media caption Murderer Aaron Barley crept through his victims' garden

"The defendant was wielding a knife, stabbing and slashing at Peter in a frenzied attack with such aggression that this alone demonstrated an obvious intention to kill him."

The company director managed to contact emergency services, and was found in the garden of the family home with facial lacerations and deep stab wounds.

Barley fled the scene in the family's Land Rover and was pursued by police before he crashed in a nearby road and was arrested.

Mrs Wilkinson, 50, was pronounced dead at the scene, while Pierce died after being taken to hospital.

Mr Wilkinson, 47, spent 11 days in hospital recovering from his wounds.

Before the killings, Barley was reported to police after his former foster carer became concerned about messages posted on Facebook, the court was told.

Among the posts was a threat from him towards his family and the possibility of a "killing spree".

Less than a week before the stabbings, the court heard, the Wilkinsons cancelled a mobile phone contract they had paid for Barley.

Image copyright Hall Green Retired Greyhoud Trust Image caption Pierce Wilkinson (left) was killed in the attack while his father Peter was seriously injured. Pierce's sister Lydia was at university at the time

The couple's daughter Lydia, 19, was away at Bristol University at the time.

She said she was warned to expect the worst and when she saw her father hooked up to "countless machines" she doubted he would survive.

When he did eventually regain consciousness, Mr Wilkinson did not know his wife was dead and was unaware his daughter had been to the mortuary to identify her mother and brother.

Both the family and police said they did not know what Barley's motive was.

'Mother I never had'

Mr Wilkinson said he had shared a "curry and a couple of bottles of beer" with Barley about a month before the attack.

"The next time I saw him he was sticking a knife into my shoulder," he said.

He said Barley had joined the family on Christmas Day last year and he wrote a card to his wife that said 'To the mother that I never had'.

"My wife was very caring and he treated her a bit like a second mother," he added.

He suggested that Barley, whose parents died when he was young, knew his life was "going bad ways" and wanted to take it out on the people that had "cared and looked after him".

Media playback is unsupported on your device Media caption Lydia Wilkinson thought all her family was dead

Det Supt Tom Chisholm said Barley has remained uncooperative while in custody and given officers no reason for the "horrific attack".

Describing the "random" murders as the most shocking he had dealt with, the veteran detective added: "There is usually a build-up or a motive or a grudge of something, but this one is just very random."

The court also heard that psychiatric reports found no evidence of diminished responsibility.

Image copyright PA Image caption Barley fled from the scene in the family's 4x4

Image caption Emergency services were called to Greyhound Lane, Norton on 30 March

Mr Wilkinson and Lydia have now moved back into the family home and said they have been "astounded" by the support they have received.

Ms Wilkinson described her mother as a "stunning" woman with a "beautiful personality".

"To have my best friend taken from me in life at such a young age is a hardship I would never wish on anyone," she said.

"Because it has to be the most awful experience. Especially when something happens… I can't ring her up any more."

She said her brother was "handsome, funny, clever" and made friends with everybody around him.

"My mum and brother were just the iconic mother/son relationship," she said.

Barley will be sentenced on Wednesday.