An eight-year-old boy has died after he suffered firearm injuries to his head and face at a farm.
A man in his 60s was arrested at the scene in Warcop, Cumbria, on suspicion of assault. He remains in custody but is now under arrest on suspicion of gross negligence manslaughter, police said.
Cumbria police said they were called to reports the boy had been injured by a firearm on Saturday at about 14:50 BST.
The child was taken to hospital by air ambulance but he died overnight.
A Cumbria police spokesman said the firearm "was secured at the scene".
They are investigating the circumstances of the boy's death.
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