Three men have been arrested on suspicion of murder following the death of another man reportedly armed with a hammer.
Staffordshire Police responded to reports of vandalism of a parked car in Longton, Stoke-on-Trent, on Wednesday.
The 25-year-old suspected of causing the damage was detained by the public in Wood Street and later died in hospital.
The arrested men, aged 20, 30 and 49, have been released under investigation.
The cause of death has not yet been ascertained and a post-mortem examination will take place on Friday. All those involved are believed to be from Stoke.
Police said it had increased patrols in the area but it was believed to have been an "isolated incident".
The matter has been referred to the Independent Office for Police Conduct (IOPC), which added that police had been responding to a report of criminal damage.
Police said CPR was performed on the detained man before an ambulance arrived.
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