Gangs of eastern European criminals are cashing in on the growing number of budget flights across Europe, to target different cities on an almost daily basis, the head of Europol told CNBC.
Rob Wainwright, the director of the European Union's (EU) law enforcement agency, said gangs - primarily from Romania, Lithuania, Poland and Bulgaria - were increasingly exploiting the freedom of movement within the region to swoop in on a city for a one-day spree of burglaries and theft and fly out the same day.
"That has helped to develop a new breed of organized crime gangs, that are now less constrained to one geographical area... they have spread their activities across countries in a way that we haven't seen before," he said.
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Within Europe, the "Schengen Area" of 26 states guarantees free movement to its citizens, having abolished passport and immigration controls at their common borders in 1995. Some 22 of the 28 EU member states are part of the group, although the U.K. and Ireland opted out.
This has enabled organized crime gangs - specializing mainly in theft - to jump on and off numerous low-cost flights, Wainwright warned, adding that Europol has seen a spike in activity over the last three years.
"Of course, the more we expand our borders, the more flights there are, the more open the internet is - all these factors, in the end, are capable of being exploited by criminals," he said.
A sophisticated operation
This type of organized crime group flies gang members to a country in the morning to carry out a succession of quick-fire robberies, before flying out in the evening. They hand over their ill-gotten gains to criminal partners in the local area, and regularly take a different flight to a different country the following day. Private homes, businesses, high-value cars, machine parts and increasingly commodities like metal are all targets.
And the gangs are surprising persistent; Europol has, for instance, recorded instances of one gang targeting 20 different countries within a short period. "This is quite a sophisticated, joined-up operation," Wainwright added.
It comes amid increasing competition within Europe's budget aviation space, with airlines such as Flybe, easyJet, and Ryanair all racing to offering new routes at competitive prices. Travelers can now easily - and cheaply - fly to and from European cities that were once relatively hard to reach, such as Pristina in Kosovo, Estonia's Tallinn, and Bucharest in Romania.
But Wainwright stressed that the airlines were not to be blamed for the rise in this type of crime, "just because they're offering a particular business model to customers. The real issue is that particular model is being exploited by criminals in the same way the internet is."
This has led to a diversification of traditional organized crime activity, according to Wainwight, with a move away from the monolithic, mafia stereotype - "although Italy still has a major problem with this traditional type."
He added: "But in the rest of Europe, there has been an evolution towards smaller, more mobile, more flexible groups, that are more entrepreneurial, and form and reform across national boundaries, for example. They are spreading their wings."
Co-ordination is crucial
Europol estimated there were 3,600 criminal gangs active in the European Union in its annual report on organized crime, published in March.
But although the agency is primarily an intelligence-gathering body, and does not have the power to make arrests, Wainwright stressed that if countries worked together, these gangs could be stopped.
"We need to make sure there is a swift exchange of intelligence - so we can get ahead of the game and identify these gangs before they strike, or at least get on the back of them as soon as they have done," he said.
"And make sure we have the means possible by which we can coordinate multinational arrest operations in the end... not working at a national level, but as a connected community."
-By CNBC's Katrina Bishop. Follow her on Twitter @KatrinaBishop
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