Meth, cocaine worth $186m shipped to Vic

Drugs worth an estimated $186 million hidden in mining machinery have been seized in another major haul by border officials in Melbourne.

The 350 kilogram sea cargo bust is the latest in a series of raids that has netted more than four tonnes of narcotics since November, including three tonnes of cocaine, 840kg of methamphetamine and 300kg of pseudoephedrine worth a total of up to $500m.

In the latest seizure, officers found 254kg of Colombian cocaine and 104kg of Chinese methamphetamine in 358 packages in a sea container which arrived on Melbourne's docks from South Africa in December.

The drugs were hidden in an iron ore extraction machine and covered with shards of charcoal, AFP Commander John Beveridge says.

The seizure, announced on Friday, began when Australian Border Force officers used new X-ray equipment to scan the container selected as part of the agency's regular detection procedures on the docks.

The AFP then watched as the container was delivered by truck to Oakleigh South where it sat until put on an interstate train. The container was then taken to a storage facility in Sydney.

Four men, including a 75-year-old South African, have been charged.

A Melbourne man, 38, and two men from NSW, aged 47 and 39, have also been charged.

They have all been charged with commercial drug offences and already appeared in court.

Cdr Beveridge said the syndicate is known to the AFP and investigations are ongoing.

An additional search in Sydney on February 6 found a compressed block of $100 notes, which authorities are still counting, the AFP said.

In other recent wins for police battling the illicit drugs trade, more than 600kg of methamphetamine and 500kg of cocaine was seized in raids across New South Wales in November and December.

Raids also resulted in a 300kg pseudoephedrine bust in Melbourne in January.