A 26-year-old man has died following medical treatment while in custody at Musgrave Police Station.
It happened in the early hours of this morning (Monday). As is normal procedure, the Police Ombudsman has been informed of the matter and has begun an investigation.
A post mortem examination will be carried out in due course to determine the cause of death.
The man was arrested on Sunday evening at around 9.30pm, after reports of a disturbance at licensed premises on the Antrim Road in north Belfast.
A police investigation into the circumstances surrounding the disturbance is underway.
Detective Inspector Stephen Harvey is appealing for information. Alternatively, information can be provided to the independent charity Crimestoppers on 0800 555 111.