A mother has been arrested on suspicion of child neglect after her 10-year-old son was found dead in a caravan in Birmingham, police said.
Emergency services were called to reports of a child unconscious at an address in Blossomville Way, Acocks Green, on Thursday morning.
He was taken to hospital where “nothing could be done to save him” and he was pronounced dead, police said.
His death is “unexplained” and a post-mortem examination is to take place.
West Midlands Police confirmed the arrested 44-year-old woman is the child’s mother.
Det Insp Joe Davenport said he understood the boy “had some underlying health issues and was admitted to hospital recently”.
“We’ve launched an inquiry to understand what happened in the days leading up to his death and to determine if any factors have contributed to his death,” he added.
A spokesman for West Midlands Ambulance Service said it was called to reports of a medical emergency at the address at 07:19 BST.
“On arrival we discovered one patient, a boy, who was in a critical condition,” he said.
“He received specialist trauma care at the scene before being transported to Heartlands Hospital.
“Sadly, it later became apparent at hospital that nothing could be done to save him and he was confirmed deceased.”
Follow BBC West Midlands on Facebook, on Twitter, and sign up for local news updates direct to your phone.