Police are continuing to question two men and a woman arrested after the death of a seven-week-old baby boy from severe head injuries.
Greater Manchester Police said they were not in a position to name the baby, who lived in the Clarksfield area of Oldham.
The 23-year-old woman, thought to be the child's mother, and a 35-year-old man originally arrested on suspicion of assault were rearrested on suspicion of murder and conspiring to pervert the course of justice.
A 26-year-old man is also under arrest on suspicion of murder and conspiring to pervert the course of justice.
"This is a tragic case in which a very young baby has lost his life and we are determined to find out exactly what the circumstances were that led to him suffering such injuries.
"News of the death of such a little boy will no doubt come as a great shock to people and I would like to try to reassure the community that we have a team of detectives dedicated to working on this investigation, and they will today be interviewing the three people in our custody.
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