Rebels boss dies in custody

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.