BRUSSELS (AFP) -- EU citizens spend more than 24 billion euros ($27.3 billion) every year on illegal drugs such as cannabis and heroin, a European watchdog said Tuesday, warning of links between the trade and terrorism.
The report said cannabis, which accounts for the biggest illegal retail market, was mainly grown in the European Union, while heroin, the second biggest market, was now being produced in some EU member states.
Alexis Goosdeel, the head of the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), which produced the report, estimated the annual spending on the illegal drugs at the massive 24 billion euro figure.
"The EU drugs market is driven by profit and power," Goosdeel said at a press conference with other officials in Brussels.
Europol director Rob Wainwright told the press briefing that about one third of all organized crime groups his organization helped identify "are involved in the drug trafficking trade."
He added that more than 20 percent of those involved in smuggling migrants to Europe were also involved in drugs trafficking.
The report warned that the Internet was making it easier to sell illicit drugs.
"The Internet has became the new battleground in the war on drugs," Dimitris Avramopoulos, the European commissioner for security and migration affairs, told journalists.
"This abuse of the Internet has to stop," he added.
The report says "many" people involved in terrorist attacks, "often recently radicalized young people, may have a history of low-level criminality, including drug use or involvement in the drug market, and exploit their criminal links to conduct their terrorist activities in a range of ways".
It warned of "some links being overlooked" as narcotics agents and counter-terror officials had separate functions and specializations.
The link between drug trafficking and terrorism is to "a certain extent indirect," Wainwright said.
"We have terrorist suspects responsible for the atrocities in Paris and we think Brussels as well who have a criminal background, a lifestyle albeit low-level," Wainwright said.
Citing the most recent available figures, the report said cannabis led in 2013 with 38% of the market, followed by heroin at 28%, cocaine at 24%, amphetamines at 8.0% and ecstasy at 3.0%.
After several years that saw a drop in the quantity of heroin seized mainly from Turkish, Albanian-speaking and Pakistani crime syndicates, supply picked up in 2013 while street prices decreased, it said.
The report estimated the number of heroin users at 1.3 million in Europe, with the annual retail market worth some 6.8 billion euros.
Wainwright said heroine production is moving within the EU, "with laboratories converting morphine into heroin that have been identified now in several EU member states including Spain and the Czech Republic."
The report said heroin is increasingly trafficked via routes involving Africa, the southern Caucasus, Syria and Iraq.
Wholesale importation of cocaine into Europe, with some 3.6 million users and an annual market value of 5.7 billion euros, remains dominated by Colombian and Italian groups, although Nigerian and Balkan dealers are gaining a foothold.
Cocaine dealers "not only use corrupt lawyers and accountants... but are believed to engage in the systematic recruitment of corrupt workers at all major seaports and airports in the EU," the report said.
It listed cocaine smuggling in maritime containers as "a major threat".