The police watchdog is to investigate the death of a 29-year-old man after "dealings" with West Midlands Police.
Kingsley Burrell Brown was detained under the Mental Health Act last Sunday after officers attended an incident on Icknield Port Road, Birmingham.
He was admitted to a unit in the city and later moved to a hospital where he died on Thursday, police said.
The Independent Police Complaints Commission (IPCC) said post-mortem test results may be known early next week.
'Disturbance at unit'
Maxi Hayles, chairman of the Birmingham Racial Attacks Monitoring Unit, told BBC News Mr Brown's family were waiting to be told what caused his death at the city's Queen Elizabeth Hospital.
The IPCC said it had started an investigation into the circumstances around his death.
Officers were called to deal with a disturbance at a mental health unit involving the same man the day before he died, an IPCC spokesman said.
In a statement, West Midlands Police said: "West Midlands Police is to be investigated by the Independent Police Complaints Commission following the death of a 29-year-old man who had had dealings with the police.
"On Sunday 27 March officers attended an incident in the Winson Green area of Birmingham and detained a man under the Mental Health Act.
"Three days later, officers were called to support medical staff at a mental health unit in the same area of the city following reports of a disturbance involving the same man.
"From there, the man was transferred to hospital but died the following day.
"West Midlands Police then referred the case to the IPCC for initial assessment.
"The IPCC has since decided to begin an independent investigation."
"West Midlands Police support this independent investigation."
An IPCC spokesman added: "Upon receiving the referral the IPCC deployed investigators to begin collecting information and to conduct an assessment.
"Following that assessment the IPCC has decided to begin an independent investigation.
"The IPCC has had an initial meeting with the family to explain our role and the scope of our investigation.
"We hope to issue further information and the findings from a post-mortem early next week."