Police are tracking 180 gangs across London in an effort to find the best ways to bring down organised crime.
Most criminal gangs are involved in several enterprises, say police
Foreign mobs, internet paeodophiles, fraudsters, drug dealers and gun runners are among active networks "mapped" by Scotland Yard.
While 47% are organised according to culture, Krays-style family-run mobs account for only 9%, say police.
Police want to find out how the gangs impact on Vietnamese, Sri Lankan and Turkish immigrants, among others.
'The greatest threat'
"It is clear that criminal networks impact on people's quality of life and increase fear of crime," said Assistant Met Commissioner Tariq Ghaffur.
"We are using the information and intelligence we have to identify the best approach we should take to tackle the networks that pose the greatest threat to communities and London."
The crackdown led by Mr Ghaffur is being backed by officers from the new Serious and Organised Crime Agency.
The intelligence report found that organised gangs could be responsible for up to 54% of killings in London.
The vast majority are involved in more than one type of crime. About 64% deal drugs and guns as well as launder money while nearly a third focus on economic crime, like fraud.
Intelligence officers found that 47% of gangs were based on cultural groups, 42% because they lived in the same area, and only 9% were family-orientated.