A mother who was suffering from severe mental health problems before she killed her three children was let down by a failing system, her friend has said.

Fares Bash, seven, Joury Bash, three, and nine-month-old Mohammed Bash died from knife wounds inflicted by their mother, Yasmeen Ali, in the early hours of 18 February 2024 in Sea Mills, Bristol.

A friend of Ali's said serious concerns about her mental health were raised with social services and health teams with calls for her to be sectioned but this did not happen.

"They all knew that she was suffering from mental health [problems], especially from 6 February," she said.

"How can this then happen less than two weeks later?

"Somebody failed. She was sick but she didn't do this without any prior warning.

"It could have been prevented," Ali's friend, who the BBC is calling Gemma, said.

In a joint statement, Bristol City Council, Avon and Wiltshire Mental Health Partnership and Avon and Somerset Police said a safeguarding review would be published in the coming weeks to ensure there was "learning from this tragic case".

If you are affected by any of the issues raised in this story, help and support is available via BBC Action Line.

Ali, who is originally from Sudan, pleaded guilty to three counts of manslaughter by reason of diminished responsibility on Friday and was sentenced to an indefinite hospital order in a secure psychiatric facility.

She was described by Gemma as someone who had previously been "very loving" and who "would do everything she could" with the children.

"They were amazing, all three of them," she said.

"[They had] so much potential - Fares with football, cars, Joury was so, so clever.

"She loved art, colouring, painting, alphabet, everything and Mohammed had just started to walk, really inquisitive, into everything.

"They loved everybody and... I loved them," she said.

But Gemma called social services and police on 6 February 2024 when she became concerned about a rapid decline in Ali's mental health.

She said her friend's behaviour had become "really, really erratic".

"Her whole demeanour, her whole character was totally different," Gemma said.

"She kept thinking there was a camera in her tumble dryer.

"She didn't sound like herself. The way she was talking, her tone of voice was very low and it was almost demonic but it wasn't her voice," she said.

Gemma said members of social services, mental health teams and the police were at the house for about five hours and they discussed if Ali should be sectioned but a decision was made not to.

"I don't know why she wasn't sectioned that night," she said. "She should never have been alone with the children."

That night, Gemma was sent a message by a social worker which said: "[I'm] quite worried, don't think I'll sleep much tonight".

The BBC understands Ali then agreed her children should be placed with another family. They were returned to her three days later.

A professional close to the family - whose identity the BBC is protecting and who saw Ali on 6 February - said they too believed she "was acting very out of character" with "signs of acute mental distress".

"I was horrified, absolutely horrified the children had been placed back with her," the professional said.

"I really struggle to understand why those children were placed back in her care, who authorised it and why she had received no mental health support.

"If she had been sectioned, had a proper mental health assessment within that week, this [the children's deaths] probably wouldn't have happened," they said.

An assessment under the Mental Health Act - to establish whether Ali required inpatient treatment - was requested but not progressed, Bristol Crown Court was told on Friday.

The judge said this was due to a lack of available hospital beds.

The assessment was then cancelled on 9 February after Ali appeared "a great deal better" to medical staff and told them she was "back to her normal self", the judge said.

The court was told Ali has since been diagnosed with a schizoaffective disorder and that Avon and Wiltshire Mental Health Partnership had written to Ali to apologise for failings in her care.

The professional spoken to by the BBC said: "There was a systemic failure, but [it was] not any one individual's fault.

"There is chronic underfunding of services that should be there to help people, but that sadly are not," they said.

A spokesperson for the Keeping Bristol Safe Partnership - made up of the local authority, police and health partners - said a Safeguarding Practice Review would be published alongside an action plan in the coming weeks.

Its purpose, it said, would be to "help agencies understand what happened, identify lessons from the case and ensure that learning continues to inform and strengthen safeguarding practice across Bristol".

Avon and Somerset Police said that a mandatory referral was made to the Independent Office for Police Conduct (IOPC) following the children's deaths, due to prior police contact with the family, but the watchdog said no investigation was required.

Eleven days after the incident on 6 February, all three children were dead.

"Five past midnight is when I get a phone call but there was no-one on the other end, there was just screaming and crying from Joury," Gemma said.

"I listened for a minute and then at some point, I don't remember when, it went quiet.

"Then I get another phone call from Yasmeen.

"She said she's going to God. That's when I called the police," Gemma said.

Bristol Crown Court was told police attended the property and could hear "screaming and chanting", with Ali discovered partially clothed with self-inflicted stab wounds to her throat and stomach.

Her three children, who had suffered "terrible injuries", were discovered dead on her bed, the judge said.

"[The injuries] are clearly consistent with you being in a psychotic state when you inflicted them," he added.

"If you've got so many services involved, then how can that happen?" Gemma said.

"The system is failing everybody. Everybody with mental health [problems]. Social services failed the family, the police failed the family and the mental health team failed the family," she said.

Gemma believes "someone needs to be held accountable" for what happened to the family.

"Fares could be preparing for secondary school, Joury could be preparing to go into juniors and Mohammed would be preparing to go to primary school, that should still be happening," she said.

Mr Justice Linden said the deaths of the children were "a tragedy" from which neither parent would ever recover.

Sentencing Ali, he told her: "It's inconceivable you would have done what you did had you been well.

"Your actions came as a total shock to those who knew you and saw you on a regular basis - you were clearly a loving mother to your children and cared deeply for them.

"For the rest of your existence you will live with the knowledge of what you've done… I'm quite sure you are heartbroken by what has happened."

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