Five police officers are being investigated for potential misconduct as part of a watchdog probe into the death of a man in east London.
Edir (Edson) Frederico Da Costa, 25, died six days after he was detained when a car was stopped in Newham in June.
On Tuesday, the Independent Police Complaints Commission (IPCC) said investigators are set to formally notify five Metropolitan Police officers that "the level of care they provided Mr Da Costa during restraint and after he became unwell may have constituted misconduct".
The IPCC said it is "now investigating this potential misconduct", but added that the serving of misconduct notices on officers does not indicate guilt, or mean that misconduct proceedings will necessarily follow.
At a post-mortem examination on June 22 a number of packages were removed from Mr Da Costa's throat.
The pathologist has not yet determined the cause of death.
The preliminary examination found there was no fracture of the neck or spinal injury, no broken collarbone, and no bleeding on the brain.
Mr Da Costa's death sparked protests in east London.
The IPCC said since the opening of its investigation, witness statements from police officers, medical staff and members of the public have been collected, as has body worn video footage of the first aid administered to Mr Da Costa.
Tom Milsom, IPCC associate commissioner, said: "We are very aware of the community concerns following the death of Mr Da Costa.
"So as well as providing regular updates to the family and communicating with the officers involved, we will, when appropriate, also inform the wider community about the progress of our independent investigation."
A Met Police spokeswoman said the force was aware that, as part of the investigation, the IPCC had taken the decision to serve notices on five Met officers.
She said: "Once the notices have been served the Met will review what restrictions, if any, should be placed on the officers.
"In reaching that decision the Met will liaise with the IPCC, as is usual.
"The Met is fully co-operating with the IPCC investigation and our thoughts remain with Mr Da Costa's friends and family for their loss."