Officers were called to an area off Strawberry Lane near Great Wyrley at 8.45am on Saturday by paramedics from West Midlands Ambulance Service, who were responding to a report of a baby in cardiac arrest, Staffordshire Police said.
An air ambulance was also sent to the scene but paramedics pronounced the child dead.
A 42-year-old man, from south Staffordshire; a 30-year-old woman, from south Staffordshire; a 20-year-old woman, from Wolverhampton; and an 18-year-old man, from Walsall, have been arrested on suspicion of murder and bailed with conditions while inquiries continue, police said.
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Detective Inspector Josh Lee, from the force’s child protection team, said: “I want to assure the local community that we are working around the clock to investigate the circumstances of this tragic incident, which has understandably caused concern.”
A West Midlands Ambulance Service spokesman said: “We were called to reports of a medical emergency near to Strawberry Lane at 8.39am on Saturday, two ambulances, two paramedic officers and a helicopter from the Midlands Air Ambulance Charity attended the scene.
“On arrival we discovered one patient, a female child.
“Ambulance staff immediately began administering advanced life support but sadly, despite their best efforts it became apparent nothing could be done to save her and she was confirmed dead at the scene.”
