ONE of Australia's alleged leading organised crime figures, Mohammad Oueida, has been arrested and charged with drugs offences as part of an investigation of a nationwide amphetamine trafficking ring.

Oueida, a multimillionaire whose light plane was among several assets seized last night, is one of the first alleged major national targets arrested as part of a renewed anti-organised crime push involving federal law enforcement agencies and Victoria Police.

His arrest will affect the Comancheros outlaw motorcycle gang, of which Oueida is believed to be a ''prospect'' or partial member, as well as a number of other connected crime syndicates.

Oueida was one of 12 people arrested in a series of raids in Melbourne's north and in Ballarat. The arrests comes after a 15-month inquiry, codenamed Operation Rossa, involving Victoria Police, the Australian Federal Police and the Australian Crime Commission.

During the raids, involving more than 200 officers, police seized a Ferrari and two other luxury vehicles, handguns, three sawn-off shotguns, an automatic rifle, 2.5 kilograms of drugs and precursor chemicals, a stolen motorcycle and equipment that police will allege can be used to counterfeit money.

Oueida has been a target of the Victoria Police and federal police since at least 2008.

At that time, relations between the federal police and its state counterparts were at an all-time low, with federal agents and state police accusing each other of compromising inquiries by failing to share important intelligence or prematurely intercepting suspects.

Relations between them are

still often hostile. However, Victoria Police, the federal police and the Crime Commission have spent the past year making a concerted effort to work together.

Victoria Police Superintendent Doug Fryer said last night: ''The result today was only possible because of the successful collaboration between all the agencies involved.''

The AFP's Melbourne office manager, Commander Scott Lee, said the operation would have a significant impact on east coast organised crime and would substantially disrupt Victoria's illicit drug supply. He also stressed the co-operation between agencies.

''This operation demonstrates the effectiveness of multi-agency collaboration and that Australian law enforcement agencies are ganging up against organised crime,'' he said.

While the arrests are significant, the operation also highlights the resilience of organised crime syndicates. The arrests are not expected to have a major effect on the supply and price of amphetamines in Victoria.

The Comancheros are one of several bikie gangs trying to expand their operations in Victoria and New South Wales, despite taking major hits as a result of recent and protracted organised crime investigations.

Last year, The Age revealed an inquiry led by the Crime Commission had uncovered an international drug network involving Chinese triads, the Comancheros and corrupt waterfront workers.

Four of the men arrested last night, including Oueida, have been charged with trafficking commercial quantities of drugs, which carries a maximum jail term of 25 years. Police said other allegations related to dealing in proceeds of crime, and possession of counterfeiting equipment and firearms.