The death of a newborn baby boy was caused by an obstruction of the airway, Lincolnshire police have said.
Officers released the detail after a 16-year-old girl was arrested in connection with the incident which happened in the early hours of September 5. She is currently helping officers with their enquiries.
Detective Chief Inspector Tony Heydon said: "Although we are unable to release any more detail at this stage we can reassure the public that we are not looking for outstanding suspects, we are simply gathering evidence and piecing together the sequence of events over the last couple of days."
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