A four and a half month-old baby looked “like something from Auschwitz” when she was found dead at her home by paramedics, a High Court judge has been told.

The little girl was “extremely malnourished”, “very underweight” and “profoundly dehydrated” when discovered in October 2013, Mr Justice Hayden heard.

She had been pronounced dead about two hours after being found, but paramedics had thought that she was dead when they arrived. One experienced paramedic called to the scene had never seen a baby in such a condition, said the judge.

Detail has emerged in a written ruling by the judge following a hearing in the Family Division of the High Court in London. Mr Justice Hayden did not name the girl, her parents, or reveal her address. He referred to her as “W” and indicated that her home had been in the Tower Hamlets borough of London.

The judge had been asked to consider a legal issue relating to baby W's father, at the High Court hearing earlier this month, following the launch of civil litigation not related to the dead girl. He outlined detail of the baby W's death in a ruling on the legal issue and said her story was “tragic and extremely distressing”.

Baby W's mother had been married in her mid-teens after being taken from the UK to Somalia, said the judge. She had returned to the UK about two years ago after becoming pregnant with baby W.

The judge said British embassy officials had helped her “escape” from Somalia. He said the mother, now thought to be in her late teens, had admitted permitting baby W's death and neglect, and was due to be sentenced soon. But he said the mother appeared to have suffered a “profound psychological breakdown” before her daughter's death.

And he said a consultant paediatrician who produced a report in the case had been “highly critical” of some agencies involved.

Dr Peter Ehrhardt said some agencies ought to have played a “more active role” in supporting the mother. In particular, he said there ought to have been greater surveillance by the Government's Forced Marriage Unit - which is run jointly by the Foreign Office and Home Office and provides support and advice to victims of forced marriage.

“One of the paramedics observed that whilst it was immediately obvious that (baby W) was skinny, he was profoundly shocked when upon cutting off her top she looked, as he put it, 'like something from Auschwitz',” said Mr Justice Hayden.

“She was extremely malnourished, very underweight and she was profoundly dehydrated. Her eyes were sunken into her head. She was of a very pale colour.”

The judge added: “This was a baby in a condition beyond which this experienced paramedic had ever seen before.

"It is a poignant fact that her weight ... was very similar to her initial birth weight."

Mr Justice Hayden said Dr Ehrhardt had filed a report and been "highly critical of some of the agencies who, in his view, ought to have played a more active role in supporting this mother". Chiefly, Dr Ehrhardt said the circumstances in which the mother came to the UK ought to have, "triggered a greater surveillance of her welfare by the Forced Marriage Unit", said the judge.

A council spokesman said everyone was deeply saddened to hear of the tragic death of the young baby.

He said: "Despite the severe difficulties her mother had been through, she was coping well with motherhood until very shortly before the death of her baby.

“The independent report has concluded that, tragically, the rapid decline of this young woman's mental wellbeing that led to the death of her baby could not have been predicted or prevented.

"Nevertheless, the report identifies several areas of multi-agency working where processes can be improved and the council and its partners are working closely to ensure these are all introduced swiftly."

Sarah Baker, chairwoman of the Local Safeguarding Children Board, said: “This was a tragic death which, because of the sudden decline of this young woman's mental wellbeing, sadly could not have been prevented.

"Our sympathies are extended to the baby's wider family and surviving siblings.

“This case has, however, identified several areas of multi-agency process which could be improved. We will improve the process by which a single professional takes the lead with each family to ensure that somebody is monitoring the 'bigger picture' of their interaction with the various services which are helping them.

"We have also made some recommendations relating to national systems and process which we hope will be considered."