Police watchdog investigates man's death in Stoke-on-Trent
The police watchdog is investigating the contact officers had with a 25-year-old man who died after being detained by members of the public.
Christopher Walters was detained in Wood Street, Stoke-on-Trent, on 15 May following reports of criminal damage.
Three men held on suspicion of murder were released under investigation.
The Independent Office for Police Conduct sent investigators to the scene and said it was also examining officers' "post incident procedure".
It said an ambulance had been called because he had become unresponsive. He was pronounced dead a short time later.
Staffordshire Police said a post-mortem investigation into his death was inconclusive.
Further tests are taking place and the cause of death is not expected to be established for three to six months.
Det Insp Alan Lyford, of the force, said: "Our thoughts are with Christopher's family at this time and specially-trained officers are providing specialist support."
He said officers believed it was an "isolated incident" but were appealing for any witnesses to contact police or Crimestoppers anonymously.
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