"Transnational Organised Crime in East Asia and the Pacific: A Threat Assessment" is the most comprehensive study ever undertaken of the subject, the UN Office on Drugs and Crime said.

Top money-spinners

It estimates that the top money-makers for criminal groups are the trade in counterfeit goods ($24.4 billion), illegal wood products ($17 billion), heroin ($16.3 billion) and methamphetamines ($15 billion).

Fake medicines ($5 billion), the black market trade in used electronics components to avoid legitimate recycling ($3.75 billion) and the illegal wildlife trade ($2.5 billion) also rank highly.

Migrant smuggling and the trafficking of women and girls for prostitution or general labour also earn crime bosses hundreds of millions of dollars each year.

Inner workings

UNODC deputy executive director Sandeep Chawla said the report opened the window on "the mechanics of illicit trade: the how, where, when, who and why of selected contraband markets affecting this region".

"It looks at how criminal enterprises have developed alongside legitimate commerce and taken advantage of distribution and logistics chains," he said.

Heroin on the up

Chawla highlighted the growing problem of heroin. Consumption is rising across the region -- estimated at 65 million tons in 2011 -- with Chinese the main users and Myanmar the key producer.

"Myanmar is the principal source of opiates in Southeast Asia. Doing something about tackling opiates in Myanmar is a very important thing for the region," said Chawla.

 "Clearly that is something that more attention can be given to with the change in government that's happening in the country at the moment."

Global health implications

Jeremy Douglas, the UNODC regional representative for Southeast Asia and the Pacific, said many of the organised criminal activities could have serious global health implications.

"Between one-third to 90 percent of anti-malarial drugs tested in Southeast Asia are fraudulent," he said, with China and India the main culprits in production.

"They do not contain what they say they do. Sub-standard drugs have two serious public health consequences: One: people get sicker or die; Two: drug-resistant strains can develop and cause a global health threat."

Power of organised crime

With rapid economic growth leading to a proliferation of criminal networks, he said the threat was now so great that it has the ability to "destabilise societies around the globe".

"Illicit profits from crimes in East Asia and the Pacific can buy property and companies and corrupt anywhere," he said.

"We need to talk about this, and organise a coordinated response now. It takes a network to defeat a network."

Knock-off goods

The trade in counterfeit goods is the most lucrative activity, despite being considered a "soft" form of crime, with China the worst culprit.

According to the World Customs Organisation, 75 percent of all fake products seized worldwide from 2008 to 2010 were from East Asia, primarily China, with the industry accounting for some two percent of world trade.

"The key players in counterfeit markets are brokers and logisticians who connect supply and demand," the report said.