The infant - who died later in hospital - has been named locally as ten month old Aiman Abbas Toor.
A man arrested on suspicion of murder in connection with the death of a 10-month-old child in Bolton has been bailed pending further enquiries.
It is believed that the child is Aiman Abbas Toor.
Shortly after 5:30pm on Friday 1 November 2019, the ambulance service was called to Crompton Street to reports that a 10-month-old girl was unresponsive.
Detective Chief Inspector Stuart Wilkinson, of GMP’s Major Incident Team, said: “First and foremost I want to extend my sincere condolences to the family of this little girl, who are being supported at this incredibly difficult time by specially trained officers.
Anybody with information should contact police on 0161 856 9908, quoting incident number 2544 of 01/11/19, or the independent charity Crimestoppers, anonymously, on 0800 555 111.