A man is dead and a teenage boy is in a critical condition after being stabbed at a skate park in Northampton.
Four people have been arrested in connection with Wednesday's incident in the Briar Hill area, police said.
They are two teenage boys, a man, and a woman all from Northampton. All remain in custody.
The man who died was in his 20s and the boy who was stabbed is in hospital with life-threatening injuries.
Northamptonshire Police have launched a murder investigation, and anyone with information - including CCTV or doorbell footage - is being urged to come forward.
Detective Chief Inspector Torie Harrison said: "This is a tragic incident in which a man has sadly lost his life, and a teenage boy is in a critical condition. Our thoughts are firmly with both their families at this difficult time."
Officers are "working at pace to establish what has happened", the inspector continued, but added: "I would still appeal for any witnesses or anyone with information who has not yet come forward, to please do so."
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A police cordon remains in place at the park in Ringway and house-to-house enquiries are set to continue.
Locals are asked to avoid the area where possible.
(c) Sky News 2026: Man dead and teen critically injured after stabbings at skate park in Northampton
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