Dylan Garbe-Ashton died after being detained by police
The death of a 20-year-old man after he was detained by police is to be investigated.
Dylan Garbe-Ashton was stopped by Dyfed-Powys officers on 22 November and taken to Newtown police station.
After arriving in a police van, he became ill 20 minutes later while at the custody desk and died the next day in hospital.
The Independent Office for Police Conduct (IOPC) is investigating the circumstances.
IOPC director for Wales Catrin Evans said it was a "traumatic incident" for everyone involved and investigators are establishing what happened.
This has included gathering evidence from CCTV and body-worn video as well as taking accounts from witnesses.
She added: "As Mr Garbe-Ashton sadly died in hospital hours after being detained by police, it is appropriate we independently examine all the circumstances."
A post-mortem has taken place but the cause of death is still unknown as further tests are ongoing.