New Rebels bikie president Jamie Ginn has died suddenly at the Perth Watch House.
Gang Crime Squad detectives took the 50-year-old into custody in Gnangara around 1pm on Tuesday.
He was then taken to the Perth Watch House where he was charged with a number of drug and firearm offences.
Around 7pm, Ginn reportedly had a seizure inside his cell.
"Immediate medical assistance was provided until the arrival of St John WA, however, the man could not be revived," a WA Police spokesperson said.
"The death is not being treated as suspicious and as per standard protocol officers from the Major Crime Division will prepare a report for the Coroner."
Ginn's death comes less than a week after an alleged gangland shooting in Baldivis.
Two Rebels bikies have been charged over the alleged shooting that targeted Mongols bikie Adam Wragg.
Shire of Murray celebrates outstanding citizens
Outstanding community members honoured at Rockingham's 2026 Community Citizen of the Year Awards
Public urged to remain vigilant after guns stolen from Pinjarra property
Mandurah's local heroes recognised at 2026 Community Citizen of the Year awards
Mandurah teacher admits to sexually abusing former student from age of 12
Man charged after allegedly stabbing man, pushing couple down stairs in Silver Sands
Firefighters continue to battle raging bushfire near Boddington
Waikiki P-plater charged with reckless driving along Kwinana Freeway
Police investigate Peron scrub fire