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.
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