A health worker has been arrested on suspicion of poisoning a child following the youngster's tragic death.
Police said the 27-year-old woman was arrested last Thursday, hours after the death, on suspicion of administering poison with intent to endanger life.
The suspect, reported by The Sun to be a nurse, has been suspended by Birmingham Children's Hospital and released by police pending further inquiries.
A police statement said: "We've arrested a 27-year-old woman in connection with the death of an infant.
"The child sadly passed away on Thursday at hospital.
"The woman was arrested on Thursday evening at a property in the West Midlands area on suspicion of administering poison with intent to endanger life.
"She has been released while the investigation continues and the results of forensic tests are examined.
"The family of the child are being supported by specially-trained officers."
A spokesperson for Birmingham Women's and Children's NHS Foundation Trust said: "Following the death of an infant at our Paediatric Intensive Care Unit at Birmingham Children's Hospital, we have asked West Midlands Police to examine what has happened, in line with our own safeguarding policy.
"The staff member involved has been suspended by the Trust after following the national process on the sudden unexpected death of a child.
"We are supporting the infant's family at this distressing time and ask that privacy is respected during this process."
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