A man and a woman have been arrested on suspicion of murdering a 18-month-old boy in Birmingham, it has emerged.
Officers were called to a property in Nightingale Avenue in Castle Bromwich just after 05:00 GMT on Wednesday following reports a child had collapsed.
Ambulance crews tended to the boy but were unable to save him.
The woman, 25, and man, 29, were originally arrested on Wednesday on suspicion of wilful neglect.
They were subsequently arrested on Friday on suspicion of murder. They have since been released on police bail.
The boy's identity has not yet been released.
A police spokeswoman said she expected post-mortem test results to take "some time".