A baby has died after being rushed to hospital, with a 31-year-old man arrested.
The child became unwell at a home in Blaby, Leicestershire.
Reports of an incident prompted the response of several emergency vehicles on Sycamore Street on Sunday (January 15).
Leicestershire Police confirmed at the time that it was supporting "other agencies" in response to a child who had become unwell.
The infant was subsequently taken to hospital and the force has now confirmed that the child has since passed away.
Brit 'saw her insides' after being cut open by propeller on luxury diving tripThe man has been arrested on suspicion of causing/allowing a child to suffer serious physical harm or death.
A 32-year-old woman was also voluntarily interviewed under caution.
The circumstances of how the baby became unwell and what caused the death are under investigation, of which enquiries are in the early stages.
Officers are urging people not to speculate, reports LeicestershireLive.
A spokesman for the force said: "A 31-year-old man was arrested on suspicion of causing/allowing a child to suffer serious physical harm or death and has been released on police bail.
"A 32-year-old woman was voluntarily interviewed under caution in connection with the incident.
"The circumstances of this incident, how the baby became unwell and what caused the death, are under investigation and we would ask people not to speculate about what has happened."