Gangs smuggling people made up to €6 billion last year, according to Europol, the EU’s police agency.
Its report went on to say that most of those profits had come from trafficking migrants into Europe.
The agency warned that people-smuggling is the “fastest growing criminal market in Europe” and its funding “is set to double or triple if the scale of the current migration crisis persists in the coming year”.
More than 12,000 suspects in smuggling gangs have been identified in the past year by Europol and police forces in Europe and abroad.
The criminals come from a host of countries, including Bulgaria, Egypt, Hungary, Iraq and Kosovo.
Their efforts are often concentrated in “hotspot” cities along the Balkan route from the Middle East, such as Istanbul, Athens and Budapest and around major hubs, such as Berlin, Calais, Zeebrugge and Frankfurt.
In addition to actual smuggling, the gangs get involved in an array of illegal activities, including bribery and forging documents, the report revealed.
Little evidence, however, was found of "terrorist suspects" using smugglers to enter the continent on a significant scale.
"Far less than 0.01% of terrorist suspects have had migrant links," Europol director Rob Wainwright told a news conference.
Europol has now created a new centre to coordinate the fight against the smuggling of migrants. The centre will help police forces from around the world share intelligence and will assist with emergency police should new migrant routes open up.
