A police operation has confirmed the notorious Mongols outlaw motorcycle gang has patched over the Finks in Western Australia.
Police Commissioner Karl O'Callaghan flagged concerns last week about the US-based bikie gang taking over the Finks and said police had been monitoring the situation.
There were previously only three Mongols in WA and all are in prison.
There are about 12 Finks members in WA and about half are in prison, while their club house has been frozen.
Deputy Commissioner Chris Dawson told reporters on Sunday that police were monitoring all gangs and played down the threat of the Mongols, who have a violent rivalry with the Hells Angels in the US.
"Irrespective of what they call themselves, police regard them (all) as criminal gangs and will continue to treat them as such," Mr Dawson said.
Laws allowing WA police and the state's corruption watchdog to declare bikie gangs illegal were passed by parliament late last year, but have not yet been proclaimed.
The intelligence was gathered as part of a national day of action against outlaw motorcycle gangs.
Police executed search warrants throughout Perth's metropolitan area on Saturday targeting two club houses and residences in Woodvale, Aveley, Balga, Henley Brooke, Butler, Ocean Reef, Landsdale, Quinns Rock and Wilson.
Seized items included a baton, a tracking device believed to be used for vehicles, 28g of white powder that is yet to be identified, and $56,000 in cash.
Further operations were carried out at licensed premises in Fremantle, Burswood and regional areas.
Charges included disorderly behaviour, five counts of possessing a prohibited drug and possessing a smoking implement.
In a joint operation with the Department of Corrective Services, 71 prison cells occupied by gang members were also searched and prison contraband was seized.
Nationally, 53 people were charged, 79 search warrants were executed and 362 licensed premises were patrolled.
Mr Dawson said the operation was successful despite a small haul in WA.
"The outcome of the operation is not necessarily the volume of what is seized, but it's the effective policing and the gathering of any evidence," he said.