The Independent Investigations Office of BC is scrutinizing its first case in the Lower Mainland, after a man died in custody of Vancouver police Sunday night.

Police arrested a 51-year old man, who they said was intoxicated, at 6:45 p.m. in connection with a disturbance on West 7th Avenue near Laurel Street.

Officers took him to a detox centre, where, according to police, he was turned away because of his history.

Police then decided to take the man home. Shortly after they arrived, he fell unconscious and officers called for an ambulance. The man died in hospital shortly after.

The IIO is investigating the incident and a team began canvassing the neighbourhood Monday.

The coroner has yet to determine the cause of death.