When a commercial trawler sank off Victoria with four crew members needing rescuing, police became suspicious about an alleged drug trafficking operation.

Nine men are accused over a conspiracy to import tonnes of cocaine and methamphetamine before distributing the drugs across Australia using trucking connections.

A 10-month investigation by the Australian federal police, Victoria police, Australian Border Force and the Australian Criminal Intelligence Commission resulted in the arrests of the men, eight of them in Victoria and one in Sydney.

The alleged criminals, aged between 31 and 72, have been hit with a variety of charges relating to drug trafficking, and seven face the possibility of life in prison if convicted.

Police were first alerted to the alleged syndicate when four crew members were rescued from a commercial trawler which sank off the Victorian coast.

The crews’ movements were monitored after police became suspicious about why they had travelled out to sea in bad weather and were without the usual commercial fishing equipment.

It is alleged the group tried to travel into the Bass Strait multiple times to a drop zone where they would have received significant quantities of drugs from a “mother ship” travelling through Australian waters.

A supplied image of a boat in Melbourne allegedly linked to a drug importation syndicate. Photograph: PR HANDOUT

Police say these attempts were unsuccessful.

But four of the men were also charged in relation to the separate seizure of 30 kilograms of methamphetamine in Perth last August and 41kg of cocaine in regional Victoria days later.

It is alleged the syndicate was using connections in the trucking industry to move the drugs between states.

Organised criminals were sending their business to Australia because of the “insatiable” demand for illicit drugs and a willingness by the community to pay top dollar for them, AFP Det Supt Ray Imbriano said.

“These are not harmless substances and apart from the health consequences, drug importations fuel violence between rival gangs in our suburbs,” he said.

“This violence too often leaves innocent Australians caught in the crosshairs.”